Kallen Kōzuki

"Snap out of it, Lelouch! You're Zero now! You have an obligation! You have to live up to the dreams you once gave us all! So please, keep fooling us until you no longer can! We need you to be Zero this time with all your heart. Play your role like you mean it!"

- Kallen Kōzuki

Kallen Kōzuki (紅月カレン) is one of the main characters featured in Code Geass: Lelouch of the Rebellion, as well as one of the two protagonists of Code Geass: Lancelot & Guren. She is officially known as Kallen Stadtfeld (カレン・シュタットフェルト), and goes by this name at school, but prefers her mother's maiden Japanese name during her revolutionary (now military) activities.

Ami Koshimizu won "Best Actress in supporting role" for her role as Kallen at the first Seiyuu Awards in 2007. Kallen was awarded 8th place in the 29th Anime Grand Prix, then 17th and 16th, respectively, in the following two.

Appearance
Kallen is a young woman who has a slim yet strong build, a well endowed figure and fair skin. She has an average height, being shorter than Lelouch but taller then C.C. Her most distinguishing features are her big blue eyes and her short red hair which are naturally spiky and that she usually adorns with her late brother's headband, even though she can comb her hair straight mostly whenever she has to use her Stadtfelt persona, like at school, for example. In term of outfit, She dresses in various ways; Her most used colors are Red, pink, and yellow, red being her main color whenever she uses the Guren. The first time we meet Kallen as a member of the resistance piloting a Glasgow she is wearing a brown combination, made of a short and an upper part, open at her midsection, that she wore with a wool red crop top underneath. Wool red armtight and long brown boots complimented the look.

After that, as a black knight she wore a black jacket with a black short both trimmed with grey lining and long black thigh high boots; Of the Black knight members she is the only one wearing a short and this type of boots. Underneath her black knight uniform Kallen wears a small pink tube under a short yellow vest with pink tight highs. As the pilot of the Guren Mk II she wears a red skin tight pilot suit, with detachable arms and zippers on the front; Her first version of the suit also has a grey life saving jacket while the second had spiky shoulders. As Kallen Stadtfeld in school, she is wearing the student school uniform, a black short skirt with a white shirt and a tie, with a beige school jacket; She customizes her look with light blue tight highs. At home, we've already seen Kallen wearing a purple shirt and a white skirt.

Other than that, in various moment of the anime Kallen has different change of outfit; she wears Lelouch's black armless top, brown jacket and black pants after a shower scene, she wears a pink bunny outfit with bunny ears and pink heels when she works at Babel tower, and occasionally wears Lelouch's black school jacket with it; She wears a short pink dress with white lining, a white collar, a yellow bow and a Blue jacket with middle length socks and heels when she goes to meet Lelouch in Shinjuku and also wears a Britannian wide skirt, yellow dress with red designs and a big red bow when she is taken as a prisoner by Britannia; She also ends up wearing both the female and male prisoner's outfit within the show. We can also see her wearing an oriental dancer outfit and a pink cocktail dress in picture drama 9.34 and 7.19.

Personality
Kallen's general personality is that of a strong willed, determined, loyal and brave individual, who can also be quite short tempered and impulsive at times; She is also compassionate, quite sensitive and truly gentle to those she cares about, and has a strong sense of justice. While being presented as a cheerful kid through past pictures within her house, she doesn't show much of this side of her anymore within the show, being fully focused on the rebellion and her determination to take back what Britannia took from her and her people.

In her Stadtfeld persona, Kallen is a demure, shy and well behaved young lady, having a fair share of friends despite being almost never present at school, even though she doesn't like playing this part and holds some prejudice against Britannians in general. While being both Japanese and Britannian, Kallen had the ability to live a normal life. However, she refused to fully accept her Britannian side as it would mean abandoning her Japanese friends, people, and self; Thus making her one of the few selfless characters in all the series, selflessness which will culminate at the end of the anime when she will have to face the one she loves for the sake of the world.

On multiple occasions at the beginning of the series, she had claimed that she hates Britannians, though that was clearly an exaggeration as Kallen has been seen caring about Britannian civilians on multiple occasions, a prime example being her visible concern for the Student Council during the Lake Kawaguchi incident. Her character arc can be summarized as thus: she transforms from an emotional, somewhat prejudiced, untrusting girl in a tawdry rebellion into a confident, capable fighter with a much stronger sense of justice and morality, willing to put aside her feelings and interests to protect the greater good.

In battle, Kallen has a very aggressive way of fighting, enjoying close range combat  and being often ruthless, and very opportunistic. Her code name, Q-1, is a shortened version of the "Queen" on a chessboard, the strongest piece in a chess game. She can be very confident in her Knightmare piloting capabilities as well as her own abilities and rightfully so - her Guren annihilated most of Cornelia's forces during the Battle of Narita, and could even defeat two powerful Knights of the Round in later battles. However, despite being one of the very best pilots in the series, if not the very best, if her official profile on the Complete Guidebook is to be trusted, she is not indestructible; as shown by her eventual draw with Suzaku in Turn 25, and her being captured in Turn 10 because of the lack of energy refill for her Guren.

Kallen's regret message reveals that she was fighting without any hope that things would come out of it and was convinced she'd eventually die, but her journey by Zero/Lelouch's side renewed her hope and her loyalty for Japan eventually ended up being loyalty to Lelouch alone, because of what he offered her, as she also fell in love with him because of that.

As a teenager, Kallen is fairly innocent when it comes to romance as she has never even had her first kiss yet and will end up very flustered whenever subject like love or flirting will come to her ; She can sometimes show some tsundere trait, especially toward Lelouch Lamperouge, while developing a crush toward his alter ego, Zero. Also, even though she disagrees with Suzaku and somewhat considers him a traitor and will try to kill him at various moment, she still treats him with respect, as she thinks they both want the same things for Japan ultimately.

Character Outline
Kallen is a young Britannian-Japanese woman, who believes herself to be Japanese at heart and prefers to be known by her Japanese mother's name. Her mother is an Eleven who stayed with her children for most of their lives. Her brother, Naoto Kōzuki, with whom she had a deep connection, was a former leader of a resistance group before his death. After his death, Kallen became a member of the same guerilla resistance group against Britannia, which would later be reformed into the Order of the Black Knights by Lelouch vi Britannia several years later. While in battle, she wears her deceased brother's headband as a memento. Kallen's combed-down hair and lack of a headband separates her frail-girl image from her rebellious personality.

Her father is a Britannian noble who comes from a prestigious family. Because his legal wife, Mrs. Stadtfeld, could not bear any children, Mr. Stadtfeld requested his former lover to allow him to formally adopt Kallen into his household as his heir. Since her daughter would benefit from being a Britannian noble, Ms. Kōzuki accepted his request without Kallen's consent, much to her displeasure. Though Stadtfeld's wife ordered her never to see her daughter again, Ms. Kōzuki refused, fighting hard to be hired as a maid into the Stadtfelds' household in order to remain by her daughter's side. This was something that Kallen was unaware of at that time.

Both Kallen's stepmother, and mother live with her in the same house, but her biological mother was often mistreated by both her stepmother, the other maids (who were all pure Britannians), and even Kallen herself after their relationship became strained. However, she would try to discreetly help her mother at times, but still stayed away from her. Since then, Kallen attends Ashford Academy, where she is a member of it's student council and is one of its most outstanding students. Despite this, she skipped school regularly as a result of participating in terrorist activities with an excuse of poor health.

Kallen is the most skilled fighter in Lelouch's army despite also being the youngest member, being referred as the Ace of the Black Knights and is also captain of the Zero Squad, Zero's personal elite guard. While Kallen is determined to fight for justice, she is seen at numerous case, questioning herself about the righteousness of her actions. The most notorious moment of doubt and resolve was during her talk with Zero in Stage 13, after she learned that Shirley's father died because of her actions.

Code Geass: Lelouch of the Rebellion
Kallen appears early in the first episode, as she is with the driver of the truck who throws Rivalz's and Lelouch' s side care off the side of the street, being pursued by Britannian forces after she and her comrades stole what they believe to be a gas capsule which actually contains C.C. inside. As their truck crashed when trying to avoid killing the boys, Kallen chose to take action and goes inside the back of the truck, where Lelouch is hidden, to take control of a Glasgow to fight off the purist faction, led by Jeremiah, who is after their resistance group.

After Lelouch gains his Geass from C.C., he takes possession of an enemy Sutherland and gets in contact with Kallen who has been fighting Britannian forces to help her escape her enemies; While suspicious at first, Kallen choses to trust him when he promises her victory and follows his instructions until she manages to force Jeremiah to ejection. While Lelouch afterward further directs the remaining resistance forces using chess strategies, and names Kallen Q-1 after the queen piece, for she is the strongest of the small resistance army, Kallen and her group slowly gain advantage until the arrival of Suzaku Kururugi with the Lancelot, who turns the tide of the battle in Britannia's favor once again.

As Lelouch's Sutherland is noticed by Suzaku, Kallen manages to save him as he is about to be slain, calling it payback before being forced to retreat anyway. Later, she joins the remnants of her resistance group in a warehouse where the surviving citizens of the ghetto have gathered to seek shelter from the Britannian military. The troops eventually discover their location and are prepared to kill them before receiving Clovis's order of a ceasefire. Kallen leaves Shinjuku with the other Eleven survivors and takes a last look at the viceroy's G-1 Base. After this incident, Kallen is sitting down and talking with a group of girls in class. Lelouch recognizes her even though she is very different from the girl he saw in the truck. As Rivalz notices Lelouch staring at her, confusing it with interest, he explains she is Kallen Stadtfeld, a top student who is barely present in school due to her frail health. She is demure, reserved, and as the heir of her family, very rich.

Lelouch then chooses to attempt to confirm his suspicions. During lunch, as a hornet comes and bothers her and her group of friends' meal, Kallen goes to hide behind a bush, complaining about her frail persona when she is surprised by Lelouch who just saw her kill the bee; Taking his chance, Lelouch geasses her into answering his questions. He then learns that she is indeed the same girl he met in Shinjuku and that she is half-Japanese and half-Britannian. As he asks her why she would go this far, we never hear her reply. As his geass comes to an end, Lelouch prepares to retire but, to be sure, tries to geass her into not mentioning Shinjuku. It fails and Kallen immediately turns suspicious and asks him why he is talking about Shinjuku; Being caught off guard he uses Shirley's interruption who called them for school, to run away.

During a call with Oghi at school, as they wonder about the voice in Shinjuku, Kallen begins to wonder if it might be Lelouch, and at the next class, she tries to pay serious attention to the tone of his voices; Lelouch, noticing she is watching him, choses to act before she understands too much while Kallen decides she has to act if he knows her real identity. After classes, Lelouch ask Kallen if she'd be okay to accompany him somewhere, to which she agrees, as she was expecting him to ask her, leading various girls, including Shirley, to squeal in misunderstanding.

While they think they are finally alone to talk in the Student council ballroom, they are interrupted by the Student Council who was preparing a party for Kallen; Indeed the director noticed Kallen isn't part of any club, which is an obligation in Ashford, and asked Milly to integrate her in the student council. Kallen then gets to meet the whole student council, as well as Nunnally. As they begin to celebrate, Rivalz proposes to toast with champagne, leading Shirley to try to take the bottle off of him for they are too young to drink that; Rivalz then throws the bottle to Lelouch, leading Shirley to throw herself at him while he tries to keep it out of reach, leading the bottle to be shaken, the cork to pop open, and the champagne to come out in a geyser, spraying all over Kallen who was right behind Lelouch.

Kallen eventually ends up in a shower and uses this situation to her advantage in order to find out if Lelouch really is Zero as he brings her some of his clothes for change. Lelouch creates a cunning deception to ease her suspicions of his identity by playing a recorded message of himself as the voice of Shinjuku on the telephone to give her a meeting the next day in Tokyo tower, with the help of a Geassed Sayoko, drawing her suspicions out of him. Their face off ends up with a very flustered Kallen hiding in shame for she pulled the curtain open in her haste and Lelouch had a full view of her body in the shower. After this incident, when both returns to the student council room, they learn the death of Prince Clovis through the media, as well as the fact that Suzaku Kururugi is the one accused of the murder.

After receiving the call from Zero, Kallen goes to Tokyo Tower and being lead by him through mobile phone, as he questions her views of her surroundings and of the city, she and her fellows resistance members eventually meet the masked leader aboard the subway. Even though he claims he wants justice and wants them to work together, the fact he refuses to shows his face doesn't motivate Kallen and the resistance group to put their trust on him, he then promises to show them a miracle so they'll know of what he is able to do.

At twilight, only Kallen and Ohgi come at the meeting set by Zero, as the others don't trust him; Even though both doubt him, they chose to help him to try and save Suzaku; Lelouch eventually manages to save the young man as Kallen drives the car where Zero reveals himself to the world and to the Britannian army, and while Suzaku and Zero are talking, Kallen, Ohgi and the other resistance members, who have joined them, chose to believe in Zero as he did something impossible to do. This is the beginning of the Black Knights.

Back to school, Kallen tries to ask Lelouch is there is a way to contact the voice who called her in the bathroom for she needs to join him; As Lelouch replies negatively to her, he notices C.C., who just came back from the dead and set herself up in his house, prancing around school in his clothes; As Kallen is about to check on what he is looking he forcefully grabs her head, leading it very close to his own, as Shirley goes by in the nearest building, catching the whole scene and confusing it with a kiss. As C.C. leaves, a flustered Kallen asks Lelouch what he thinks he is doing to which he answers evasively. Always in school, as Arthur, the stray cat Euphemia and Suzaku found, wanders through the Lamperouge house, he gets his head stuck within Zero's mask and ends up running through school with it on, leading to a merry cat chase at school; As Lelouch is worried that Kallen might see the mask and suspect him again, Kallen is panicked because the president of the student council, Milly Ashford, just launched the whole school into the cat chase, hoping to learn about one of Lelouch's secret, and the prize for the one who captures the cat, she has offered a kiss from a member of the student council.

As Kallen sees a lot of guys running after the cat in the hope of getting a kiss from her, she freaks out as that would be her first kiss and tries to run and capture the cat while still having to maintain her ill persona; She eventually bumps into Shirley and they chose to work together to capture Arthur. As they are about to catch him, Shirley suddenly asks on who Kallen will use her kiss, for she is worried Kallen might kiss Lelouch; While the girls argues, the cat flees. Eventually Suzaku catches the cat after the Zero mask is safe and hidden from everyone and the other students realize that Lelouch and Suzaku know each other, before welcoming Suzaku in the student council.

After the cat chase incident, as the student council is welcoming Arthur the cat amongst them, Shirley tries to confront Kallen again about Lelouch, as she thinks they are secretly dating, leading the terrorist in hiding to minimize the kiss, leading to yet another misunderstanding from Shirley who imagines Kallen already did more than just kissing. A flushed Kallen tries to stop Shirley's assumptions and eventually storms out the room as Suzaku enters.

Back to the resistance, as the resistance members are gathering around Zero in their new headquarters, an oversized camping car, they hear on the news that the Japan Liberation Front has decided to act and are holding Britannians as hostage in an hotel jacking ; As the camera fan out, Zero and Kallen recognize the student council members amongst the hostages, as they were out on a trip. While Kallen is worried about them, Zero choses to take action and eventually uses the hotel jacking accident to liberate the hostage and officially introduce the Black Knight to the world, calling upon the weak to rally them and for the strong to fear them.We get back to Kallen as she is back to her house, sleeping soundly after a night of activities with the black knights when she is awaken by a strong sound; In the hallway, a maid fell from a ladder while trying to fix some lighting ; As the maid apologizes and asks Kallen if she made new friends at school for she has been going a lot more recently, Kallen shuts her off, telling her it's none of her concern before closing the door, whispering to herself " Leave"

As she is tired of her double life while walking in school, she hears shouting from a room, and as she enters, she is greeted by the student council members being disguised as cats, gathered around Lelouch who is tied up to a chair as they try to apply make up on him. They explain to her it's the welcoming part for Arthur the cat and as Shirley tells Kallen she prepared costume for her, Lelouch barges in, snarkily saying that Kallen doesn't need a costume as she is already in disguise; After Kallen snaps back the conversation goes on about the hostage situation and everyone being safe, leading Kallen to realize she saved everyone. As Kallen goes on about her day she monologues about how the Black Knights are growing more and more popular and how she wishes she could know who Zero is, but fears he might disappear if being forced to reveal his identity.

Back to her house, Kallen receives a visit from Milly; As Kallen's stepmother comes in and criticizes Kallen's frequent nightly escapes while her father is absent, Kallen reminds her she is taking full advantage of it as well; They are interrupted by the same maid as before who just broke a flower vase. Milly, who came in to bring Kallen her grades, at the demand of her grandfather now knows she is half Britannian and half Japanese; She then learns that Kallen is living with her stepmother and that the maid is her biological mother, so it's an unusual case of the official wife, the lover and the daughter of the lover living together. Kallen confesses she thinks her mother is annoying and thinks it's pathetic how she forces her presence alongside her former lover. Milly promises to not spill out the beans and advises Kallen to take care of herself as this can be heavy to bear, even though Kallen thinks it's not that awful.

The next day, as she is walking through the city after school, she, talks on the phone with Oghi about a new drug called Refrain which has been targeting the Japanese as it helps the user to relieve happy past times; After she hung up, her attention is caught by an eleven merchant getting beaten down by Britannians ; While she wants to intervene, Lelouch, who was around, stops her and tells her she won't be able to do anything given how many they are and how it could also brings the merchant more trouble since he usually works here. As their talk attracts the attention of the delinquents, Lelouch uses the occasion to geass them to go and have fun elsewhere, Kallen runs to the merchant to see if he is alright, but she ends up distraught to see the merchant basically bowing down and asking her if she and her boyfriend would like to buy something to eat ; He is basically like her mother, who has to work as a maid in the house of her former lover and endure all the humiliation that comes with that in order to survive. After that Lelouch and Kallen have a talk while sitting on a bench about the change that occurred when Japan became Area 11 and how things have gotten better in some aspect but are difficult to handle because of the pride matter. Kallen then asks Lelouch what he thinks about this whole situation and what he plans to do about it ; Lelouch tells her he’d rather do nothing, as it's more simple and easy for the Japanese to endure and to be able to survive like that. This reminds Kallen of her mother and in anger she slaps him, being disappointed by his lack of human decency and storms off.

At night, before the Black Knight begins an operation under Zero, Kallen muses over the rightfulness of their actions under Ohgi's curious gaze. As the Black Knights eventually attack a Refrain drug dealing platform, Kallen storms in with a Knightmare, noticing how much leverage even a single one can give them; as she storms in a room, she comes face to face with junkies users who are high on Refrain. She then notices her mother, who is daydreaming about the time when her brother was taking care of her little self; Kallen is pissed off at her mother's weaknesses who has been relying on men and drug, and as she is about to snap at her, she is attacked by a Knightmare from the Knight police. As Kallen tries to flee from the attack, she notices she is still holding her mother, and even though she doesn't want her, she can't force herself to get rid of her; As the Knightmare takes advantage of the fact she can't fight as she is protecting her mother, Kallen yells at her mother to run, leading her mother to tell her she is here, by her side.

Kallen understands her mother stayed in her father's house for her and that she was the mean one. She eventually manages to defeat the Knightmare, and as she runs to her mother, under Zero's stare who understands she is her mum, C.C., standing in some upper area notices how fake tears can hurt others and fake smile can hurt oneself. Eventually Kallen's mother's mind is fried out by the drug and she is sentenced to 20 years in jail for drug use. Kallen then promises her she will change this world before she comes out. After that we have the beginning the the real Black Knights operations, the Kyoto group have entrusted the Black Knights Knightmares, including a powerful red mech dubbed the Guren Mk2 ; As everyone admires it and leaves to take care of the various new recruits, Zero comes out of the shadow mentioning how everyone is glad about the support Kyoto gave them even while they also support other resistant cells; Kallen also thinks it’s a good thing but Zero tells her it’s nothing but a test, to which she replies it's still great to have their attention ; Zero notices her optimism and send her the Guren MK2 keys, offering her the Knightmare; Kallen doesn’t understand as he is the commander but he reminds her she is their ace pilot, their most powerful asset, and that she has a reason to fight ;

We then get to the fight in Narita where Kallen takes command of the Guren MK2 for the first time and launches the radiation wave leading to the landslide, plays her part as Zero’s bodyguard and face Jeremiah, Cornelia and Suzaku with her Knightmare. As the fight gets complicated and Zero orders them to retreat, Tamaki notices they abandoned the JLF members as bait, to which Kallen agrees even though she doesn’t like the way he presented that. At the end of Stage 11 as she comes to bring Zero back, Kallen eventually meets C.C. and frowns when Zero mentions she is a precious accomplice of his.

After that, as they are gathered in their headquarters, Tamaki begins to question Zero’s identity again ; Kallen strongly reacts and defends his results which matters more than his identity. We see later the resistance group talking about how they were initially Naoto’s group and how the fact that his little sister sided with Zero, and that Ohgi gave him the lead almost forced them to follow him. While Zero is alone in his office, Kallen knocks and apologize for the scene before, Lelouch then asks her if she’d like to know who he is as well, leading Kallen to muse about C.C. who knows his identity, before telling him that’s not the case before she leaves.

We then move to the aftermath of Shirley's father death which was caused by the landslide Kallen caused under Zero's orders; Kallen, feeling guilty, once again begins to doubt her actions are the right ones. During a meeting with Zero, she tries to call him but he tells her they’ll talk later. The next night, Kallen stumbles upon Zero resting in the Knightmare warehouse, with his mask off and a towel over his head to cloak his face. While she apologizes and prepares to leave, Lelouch asks her if she's having second thoughts. Kallen then sadly confides on her reasons to fight and to kill people, for she thinks it's the only way to reach her goals, before asking Zero if those deaths and their actions will really be able to change the world. Lelouch then says they will, no, they must, and then explain it's the only path and that for those deaths to have a meaning, more have to come and they have to use the worst means to meet their ends even if they have to go through with slaughter ; He then adds this is the reason why he doesn't want to pressure her into doing that, and if she wants to stop, she can, much to Kallen’s surprise; Kallen muses over his still form for a moment before giving in and smiling, telling him that they’ll go on together and that she wants to move ahead with him; leading to a genuine smile as he says « Thank you, Kallen ». Kallen ends up being very moved by his reply, smiling softly in reply.

Kallen's next appearance is during a fighting scene between Britannia and the Black Knights, with the JLF being used as bait. As Zero And Kallen traps Cornelia, Suzaku suddenly barges in and begins to fight against Zero’s Burai, as Kallen is stuck fighting with Cornelia, unable to come to his aid. As Suzaku wins against Zero, sending his Knightmare to the floor, Suzaku can’t finish him off as Kallen’s Guren jumps over Cornelia to attack him while Kallen shouts she will protect Zero before engaging in a fight with the Lancelot. As the fight is pretty even, the Black Knights receive a retreating order and the battle ends there.

Back to school, during the Mao arc, we see Kallen and Suzaku attending to Arthur’s needs as Rivalz and Nina are also there, talking about Lelouch and Shirley having a fallout. Kallen suggests to leave them be as they are constantly arguing as a couple while Suzaku, seemingly also mistaking the relationship between Kallen and Lelouch begins to question her before she tells him there is nothing between them.

Back within the resistance, Kallen and Zero, with the assistance of the Holy swords and the black knights manage to free Tohdoh from his cell, and we reach the fight against Suzaku where his identity is finally revealed, to Lelouch’s dismay and Kallen’s visible shock as she frenetically asks for Zero’s orders about the Lancelot and Suzaku. While Zero is too shaken to react, the Holy swords choose to attack Suzaku and Kallen tries to stop them by asking them to wait for Zero’s orders, but they refuse. Lelouch finally orders for retreat and they leave the battlefield.

In Stage 18, Zero announces the official hierarchy of the Order of the Black Knight. Kallen is named captain of the Zero squadron, the only team that will answer only to Zero, his personal team. While she is delighted to hear about her new position she also notices that C.C. didn’t get any role. At the same time, Suzaku is named Knight to Euphemia.

Back to school where a party is hosted to celebrate Suzaku being a royal knight, Kallen arrives, holding onto her pink pouch, the one concealing a knife and begins to move toward Suzaku, clearly intending to murder him as she thinks it’s for Zero ;But before she can reach her targets, Lelouch grabs her wrist and tell her Shirley was looking for her ; She mentions she has something to do, and as Lelouch ask her what, Suzaku notices them and join the pairing ; Kallen takes her chance to flee under Lelouch’s notice.

Zero finally orders a new mission in order to capture Suzaku alive and Kallen is relieved, knowing she won't have to assassinate him. Later, Zero confronts Diethard and ask him to not try to manipulate Kallen anymore, for he is the one who influenced her so that she’d attempt to kill Suzaku. Eventually, the fight begins in Shikine Island and a trap is set in order to capture Suzaku, who ends up trapped with his Knightmare disabled because of a gefjun net around him. While Zero talks to Suzaku while holding him at gunpoint, an order from a higher authority comes, ordering Suzaku to hold Zero hostage as they plan to bomb the zone with missile, implying he has to sacrifice himself in order to have Zero killed. As Suzaku turns the tie and hold Zero hostage, both Euphemia and Kallen try to rush toward the boys, Euphemia taking a Knightmare and Kallen’s Guren jumping in the gefjun net zone, leading to her Knightmare being fully disabled ; She then comes out of it and try to catch Suzaku’s attention as she undercovers herself as Kallen Stadtfeld in panic, while running toward the Lancelot. It all ends as the Avalon appears and begins to bomb the zone with the Hadron Cannon. Afterward, Suzaku awakens alone on an island and as he tries to find water, he stumbles upon Kallen, showering under a waterfall. As he recognizes her, Kallen notices him and charges him before being easily mastered. Suzaku then tell her she is under arrest since she is a member of the Black Knights ; While Euphemia and Lelouch are on another side of the Island, Suzaku and Kallen, on their side, manages to confront their position and point of views, Kallen talking about the meaning of her brother's death and Suzaku confessing about killing his father. The next morning both pairing eventually meet, and as Zero pretends to have Euphemia as an hostage and asks Suzaku to release Kallen in exchange of the princess, Kallen, being unnoticed by Suzaku, manages to attack him, leading to a small cat fight between Euphemia and Kallen before Suzaku manages to break free from Kallen’s grasp while a Geass symbol glows on the floor as Lelouch steps on it and leads the floor they are standing on to collapse.

They eventually all ends in front of some Geass ruins, with Schneizel, Bartley, and his scientists who are gathered and working there being witness of Zero’s arrival. Kallen notices a Knightmare and warn Zero, before fighting off some Britannians soldiers and rushing on the Knightmare as Zero takes command of it. They eventually manage to flee as the Knightmare can fly.

Back in Ashford during the school festival, as Suzaku is busy cutting off onions for a giant pizza, Kallen comes in; Suzaku then tells her he won't denounce her and wants to try to convince her through words, at least in school; Lelouch, who was coming to talk to Suzaku also notices Kallen being there and understands their agreement. He then asks Kallen to go help their class with their activities and Kallen ends up playing a living tombstone role in a horror house, at her anger. Lelouch didn’t tell her about what she had to do and she mumbles about how only Zero can give her orders. As she tries to scare the next visitors she is surprised to see Oghi, with Villetta.

In the storage warehouse of the school, as Lelouch asks C.C. to stay hidden after she came in school for the giant pizza, he is surprised by the arrival of both Kallen, Oghi and Villetta ;Lelouch fears they might see C.C. and to add even more mess, Suzaku and Shirley both come in as well. Both Lelouch and Kallen, each on their side, plan a way out for both Oghi and Villetta for Kallen, and C.C. for Lelouch. As Kallen cut out a string holding up some huge planks which begins to fall toward Shirley and Suzaku, and as both Kallen and Lelouch rushes in to save Shirley, Lelouch unleashes a huge pink smoke which invades the warehouse. Eventually Kallen ends up protecting Shirley as both Lelouch and Suzaku hold a huge plank which was about to fall onto the girls.

After that, Euphemia, who has been recognized as she came to the festival in hiding to see Suzaku, announces the creation of the Special Administrative zone of Japan, to Kallen's vivid emotion, for this is an area where eleven will be named Japanese and will have equal rights with Britannians.

The next time we see Kallen, she has been waiting outside of the special administration zone where Zero and Euphemia were meant to meet; When the Black Knights understands something went wrong and Zero orders them to attack and find Euphemia they all rush into battle. Kallen eventually manages to find Euphemia in a Knightmare, and as she is about to slay her, she is interrupted by Zero, who chose to kill her himself. After that, Zero meet Kaguya and the Kyoto representative, with both Kallen and C.C. standing beside him.

After Euphemia's death, we move to the Black Rebellion. Kallen worries about the student council and hope they are safe; Eventually, Zero choses to establish his headquarters within Ashford Academy to protect Nunnally during the fight. As the student council members don't trust Zero, Kallen, who stands behind him, moves ahead and reveals her identity to them in order to have them comply to Zero’s terms more easily, assuring them they will be safe as will other students of the school if they all stay in their dormitory.

Afterward, as she fights with a raging Suzaku who wants revenge for Euphemia, she ends up being dominated, being weakened by her inability to fly unlike the Lancelot, and while she is about to be killed by Suzaku, Zero interrupts him and save her life, before trapping Suzaku in a new gefjun net. When Lelouch learns Nunnally has been captured by V.V., he transfers command to Tohdoh before cutting off his communications, leaving Tohdoh in charge. Kallen, lost without orders, is contacted by Oghi who asks her to follow Zero, to understand why he is leaving them, and in order to help him, since he is the one who can make her brother’s dream come true. Under his advice she then follows the Lancelot who is leaving the battlefield as well, hoping he’ll lead her to Zero. This lead us to the reveal of Zero's identity when Suzaku is holding Zero at gunpoint in Kamine Island, Kallen is also there, aiming at Suzaku. Suzaku tells her she has the right to know and shoot at Zero’s mask, which breaks and reveals Lelouch’s face for his and Kallen's eyes to see. We then assist to Kallen's breakdown who totally falls apart, even on her knees by realizing the boy she despised and the leader she adored were one and the same. When she asks if he used Japanese as well as herself, Lelouch simply states that Japan would have been freed, just like she wanted and then fully focus his attention on Suzaku and on Nunnally having been abducted.

Meanwhile, Kallen rises up, body shaking, and look at her hands which are trembling, visibly stressed about what she did under his orders. As Suzaku continues to threatens him, Lelouch choses to take both Suzaku and Kallen as hostages with a liquid Sakuradite bomb planted on his chest. The season ends with Suzaku and Lelouch's facedown with Kallen in the mix and the sound of a gunshot.

Code Geass: Lelouch of the Rebellion R2
One year later, Kallen is still part of the Black Knights but due to revealing her identity, she had to leave Ashford Academy and no longer lives her double life. Along with C.C. and Urabe, she has been working in hiding for a year to try and get back Lelouch vi Britannia, who was been mindwiped by his father, Charles zi Britannia, and now live the life of a regular student without any memories of his past life as Zero or as a prince. When R2 begins we meet again Kallen as she is working as a bunny girl waitress in Babel Tower, a place similar to that of a casino, where she meets again with Lelouch who came in to gamble in company of his younger brother, Rolo. After she spills drinks of him by accidentally bumping into him, she apologizes profusely by quoting their respective status as a reason to feel bad about that, and when Lelouch asks her to not brandish his status, she replies by quoting what he said to her in Stage 9, about the weak being obliged to abide to the strong authority. As she tries to put a tracking device on him, she is interrupted by the Black King, a notorious mafia boss, champion of chess, who was on the hunt for pretty bunny girls/slaves ; Lelouch then takes his chance to defy the man in a chess match over Kallen, match that he easily wins.

As the Black King tries to have Lelouch pass off as a cheater in order to save his reputation and orders his bodyguards to restrain him, an explosion has the building shaking; Kallen takes this chance to attack the black king and his men, grabbing Lelouch's hand and running away with him ; While chaos ensues she ends up on the ground, without Lelouch and without any idea of what happened; Right after that she takes control of the Guren Mk II her fellow black knights have brought to her within the tower and begins to fight the various Britannian troops which have been sent to fight off the terrorist attack on the Tower. At the end of the episode, as Lelouch just got his Geass back from C.C. who took out the seal she put on his memories back in Stage 25, Kallen's Guren and Urabe's Gekka pierces the roof and land in front of Lelouch in a bowing manner; While Urabe asks Zero to lead them again, Kallen stays silent. After that the fight goes on, as Kallen destroys more Britannian force, Lelouch's congratulates her and ask her to go to floor 21. As he enjoys the evolution over the fight in his favor he is interrupted by Kallen who disobeyed his order and came to be with him. She then raises a gun and confronts Lelouch; He first choses to taunt her about how she abandoned Zero in Kamine Island, for she ran away after Suzaku got a hold of Lelouch, but she doesn't take the bait and interrogates him about his identity and his Geass, fearing he might have used it on her to corrupt her heart into following him, leading Lelouch to chuckle to Kallen's exasperation; He then insists that her choices are her own and that her loyalty, admiration and everything she felt was of her own volition for she has chosen him. When she looks obviously distraught Lelouch asks if she can't believe it, to which she replies she wants to, even if that means being a slave, but she'll believe in Zero, not in Lelouch, choosing to separate the two personas. Lelouch understands, then, in a change of mood, asks her if she plans on changing her clothes, looking quite obviously at her cleavage; Kallen lets out a shriek, covering herself in haste and calls him a pervert; They are interrupted by C.C. who warns them new troops are coming. While they witness those arrivals, Lelouch puts on his school jacket on Kallen's shoulders, covering her modesty to her embarrassment. They then get back in battle, Lelouch using a Burai.

While they are fighting against a new Knightmare they don't know, which seems to appear and disappear and is slowly turning the tides to battle, in Britannia's favor, Kallen, Urabe and Lelouch ends up facing him on their own ; While Urabe speaks of the fighters being replaceable and Zero's safety being the most important thing, Lelouch contradicts him and tell him their lives are valuable and they'll never win if they think of themselves this way, to Kallen's surprise; Even though, Urabe is forced to sacrifice himself in order to save Zero. As the unknown mecha still manages to survive, Kallen comes in to protect Zero, being ready to die as well, to Lelouch's visible dismay who tries to stop her; C.C. then interrupts them and announces Lelouch everything is set and all the bombs have been installed; Lelouch then forces an explosion in Babel Tower foundations and Kallen and him are able to escape.

After that, Zero makes his announcement return, Kallen watches his speech on TV, hidden in the Chinese embassy for it is proclaimed to be the new territory of Japan by Zero. When Zero comes in in his headquarters, Kallen congratulates him and discovers it was actually C.C. under the mask; C.C. then lightly mocks her for not liking being kept in the dark when Kallen frowns upon not knowing.

Afterwards, in the Chinese embassy, while getting out of a shower, Kallen muses about the dual entity of both Zero and Lelouch before confronting C.C. about the fact the green haired girl could have played the bunny girl; She then gets to meet Li Xingke and one of the Chinese eunuch who confuses her as Zero comically. They are interrupted by the TV announcement that the imprisoned black knights are about to be executed. The next day, she enters the fight to free her fellows comrades; At the end of the day she gets to hug Oghi and the others who have been freed thanks to Zero and the intervention of the mysterious Babel Tower Knightmare, piloted by Rolo. During a meeting with C.C. and Lelouch, Kallen once again confronts Lelouch about him keeping the identity of the pilot a secrecy from her to which he replies he also likes having his secrets too. She then asks if that's Zero or Lelouch talking, to which he replies that he didn't made their relationship public either, in a very suggestive way which has Kallen blushing while asking him to stop implying things. Eventually she gets her confirmation that she is still the captain of Zero's squadron and leaves the room. Kallen's next appearance is during the school festival episode, where she comes in hiding, wearing a huge green mascot costume named Tabattachi, in order to get C.C. back who has decided to infiltrate the school to retrieve her Cheese kun plushie. After a new merry cat chase involving almost everyone and Arthur, Kallen bumps into Villetta, who is now a teacher in Ashford, working as a double agent to keep an eye on Lelouch, and remembers she already saw her with Oghi. She informs Lelouch of that and thanks to C.C.'s explanation, he eventually understands that Oghi and Villetta were in a relationship managing to use that to blackmail Villetta.

When Nunnally vi Britannia is revealed to be the new governor of Area 11, Zero sets a trap to try and capture her while she is on her way to the Area; While Britannian units are now able to fly and the fight is set up in the air, the Black Knights forces are forced to fight while landed on the governess airship; During the fight, Kallen's Guren lose it's balance due to an attack and as she falls down, she receives a call from Rakshartha who brought her an update for her Guren; She then receives flight capabilities and an upgraded radiation arm. With those new equipments, she quickly make a come back, defeating Guilford, incapacitating two Knight of Rounds, Gino Weinberg and Anya Alstreim in their Tristan and Mordred, and while she is after Suzaku, the battle eventually gets interrupted because of the sinking of the airship; Kallen saves Zero before the crash.

After this incident, Lelouch falls in a state of depression, for he sees no point in being Zero's anymore because Nunnally is making her own choices and she refused to follow Zero. While he is sulking in the subway he receives a call from Q-1, who is calling him in from a dark hallway on the Ikaruga, but choses to break his phone and throw out the pieces instead of replying. While she is looking sadly at her phone on the bridge of the Ikaruga, the black knights are interrupted by Kaguya Sumeragi's arrival, who is sad Zero isn't there to welcome his fiancee; While Tamaki playfully suggests Zero might be cheating on her, Kallen vehemently denies it but Kaguya is surprisingly very welcoming of the idea, because heroes are fond of sensual pleasure; While C.C. praises her maturity over that, Kaguya thanks her for caring about Zero in her absence and decides to create the Three court ladies of Zero, including both her, C.C. and Kallen. After Lelouch geassed some delinquents, and while he is sitting on a pile of planks in a place under construction, in Shinjuku, as he is about to inject himself with Refrain he took from those, he is interrupted by Kallen who managed to found him, for she knew he'd come here cause this is where everything began and Zero was born. As she wants to talk to him about something she notices Lelouch is holding something; He confirms to her it's indeed refrain and that she must know about it, making a clear reference to her mother's addiction. Kallen then gets angry and gets at him, ripping off the vial from his hands and crashing it on the round before telling him a failure isn't the end and that he has to try again, he just has to order her around, be it piloting her Knightmare or being a bait, she'll do anything he asks. He then asks asks her to comfort him and rise up before advancing toward her, leading her to step back a little ; He then adds there are things women can do for that and catches her chin before leaning in to kiss her. Even though Kallen has a strong moment of hesitation she eventually backs out and slaps him; A very hurt Lelouch looks at her in bemusement as she asks him to get a hold of himself and to get back at being Zero, for he showed them dreams and he has to bear the responsibility of making those come true; She then asks him to lie to them until the very end before allowing a tear to fall then she runs away; After a short moment of thinking, Lelouch gets ready to run after her but is interrupted by Rolo, who followed him since Ashford. As Kallen stops running outside of the construction area, she looks back and when she sees Lelouch didn't follow her she eventually leaves. Back on the Ikaruga she has a small talk with C.C. about the weight of Zero's mask before they are interrupted by an attack.

After a trip to Ashford which allows Lelouch to fully regain his composure, he gets back to the Ikaruga calling after Q-1 to let them know he is there, before helping them to win the battle they are involved in against Suzaku's forces. When Zero gets back on board Kallen tries to speak to him but is interrupted by Kaguya who runs to him and give him a hug. After Zero organised the Black Knights exile in China, Kallen has another moment with Lelouch, as they are stationed in Horai Island; in a control room where there is just the two of them, as Kallen is standing on top of a control board she gets to think about how relieved she is to see Lelouch is better now, for she was very worried before, reminding herself of his attempt to kiss her; Noticing she turned silent Lelouch interrupts her thoughts, leading her to panic, stumble and fall on top of him on a very suggestive position, almost kissing again. She then takes the opportunity to ask him why he came back; Instead of answering Lelouch asks her if she will agree to come back to Ashford with him once it's all over; As he is about to add more, he is interrupted by C.C. who was sitting in the corner and looking for tobasco, leading the two teenagers to wonder when she actually came in. They are then all interrupted by a call from Kaguya.

At night, as the engagement party for the Tianzi and prince Odysseus eu Britannia is happening in presence of various people, Kaguya makes a sensation by coming in, for she was invited as a friend of the Tianzi, in company of Zero and Kallen. Zero, noticing everyone is there, from Schneizel to Suzaku, decides to challenge Schneizel to a game of chess with the prize being Suzaku so he can offer him to Kaguya; If he loses he'll take off his mask; Kallen reacts strongly about both events. The chess match eventually happens with both Suzaku and Kallen keeping both princes safe. Gino and Anya recognize Kallen as the pilot of the Guren, with Anya preying on her while Gino notices she is totally his type. As the chess match goes on, it is interrupted by Nina who tries to attack Zero to avenge princess Euphemia. She is arrested by Kallen who confirms she is Japanese but still shows sorrow over Nina's pain.

The next day, Zero abducts the Tianzi during her wedding and escapes, protected by his troops. As they run away from the forbidden city, Kallen notices Zero walking away with C.C. and makes an annoyed pout; Before much else happens, the Black Knights are attacked by a new Knightmare, the Shen Hu, piloted by Li Xingqe who came after them to get the Tianzi back. Kallen then rushes into battle and face the new Knightmare, even though according to some black knights members, that's too reckless for her Guren wasn't properly refilled. As the battle between the Guren and Shen Hu goes on, Kallen shows off great confidence in her skills and while Xingqe states he has to kill her, and while she is about to catch him with her radiation arm, the Guren shuts down because of the lack of energy; Xingqe then takes this opportunity to threaten her as an hostage asking for Tianzi to be given back; As the Holy swords prepares to save Kallen they are interrupted by the huge Chinese federation army who came to help Xingke, allowing him to retreat while taking Kallen with him.

As Zero realizes what's happening, he jumps over the communications to ask Kallen if she can still hear him. Kallen confirms and directly apologize, but in a rare outburst of personal concern that surprises both C.C. and Kallen, Lelouch tells her to not worry about that and to just sit tight and wait for him to launch a rescue. Overjoyed by Lelouch's words Kallen confirms she will and the communication goes off. As Oghi orders the Ikaruga to go and pursue the Chinese federation, Diethard intervenes and speaks against this idea. Facing them is the whole Chinese army and it's too reckless for they might be destroyed; He then turns to Zero and asks him to make a choice while putting his personal feelings on the side or else this would be favoritism, for Kallen is just one soldier. Lelouch, visibly distraught eventually chose to go save Kallen against Diethard's advice, to everyone's relief, including C.C.. After a complicated battle, a retreat, and another battle, Lelouch, in his new Knightmare, the Shinkiro, finally reaches his goals with Xingke's help and asks where Kallen is. Xianglin then tells them the eunuchs gave her to Suzaku, leading Lelouch to rage even more against his former best friend for taking everything he holds dear before swearing he'll get Kallen back no matter what.

During her capture, as she is prepared to die, Kallen is eventually taken in charge by Nunnally who puts her in a glass cell, gives her a yellow gown and come to talk with her from time to time; Kallen takes this opportunity to learn more about Lelouch as a brother and also talk about her own deceased brother. She also gets visits from Gino, who tries to learn more about Suzaku and also questions her rejection of her Britannian identity, for her life would have been easier if she had chosen it over being Japanese. A turning point of her imprisonment is when Suzaku threatens to drug her with Refrain after Shirley's death in order to get answers and to know if Zero is indeed Lelouch. At the last minute he pulls back, and when he comes to apologize over it later, he is be beaten off severely by Kallen who is ready to die in retaliation for hitting a Round.

During the second battle of Tokyo, Kallen is branded as objective number 2, Nunnally being number 1, and is rescued from captivity by Sayoko, just before an assassin was about to kill her. She then takes the commands of the new Guren S.E.I.T.E.N which is an ameliorated version of her Guren done by Lloyd Asplund and by Cecile Croomy which isn't supposed to be able to be piloted by anyone. She rushes into battle and decimates the Britannian forces, before she manages to save Zero who is about to be killed by Luciano Bradley and his Valkyrie Squadron; She defeats them easily and as she is asked to go after Nunnally she is interrupted by Suzaku who is after Zero. Gino also intervenes, understanding Kallen has chosen to be Japanese and asks Suzaku to let him take Kallen down to which Suzaku replies she isn't that kind of adversary. Eventually Kallen fights and break through Suzaku's defenses easily, and as she on the verge of killing him, encouraged by Lelouch who wants him dead, Suzaku's Geass command, leading him to survive by firing the F.L.E.I.J.A. bomb. Kallen dodges it but the bomb explodes, hitting the government building, destroying a fair portion of the Tokyo Settlement and killing presumably everyone who didn't manage to escape. After the explosion, Kallen gets back to the Ikaruga, to everyone's relief and asks where Zero is; She eventually joins a very depressed Lelouch, telling him the Black Knights have asked for his presence in the warehouse when she is interrupted by an amnesiac C.C. who asks Lelouch to take off his clothes so she can heal him; Confusing the whole thing a blushing Kallen asks Lelouch what they were doing while she was imprisoned, leading him to try to clear up the confusion before he falls back in his state of depression and explains C.C. lost her memories because of him. While on their way to the meeting, Kallen muses over the fact Lelouch has now lost everyone and is truly alone when he interrupts her thoughts to apologize for taking so long to free her. Kallen then speaks about how Nunnally helped her as they arrived in the warehouse, before they are interrupted by the Black Knights who set up an ambush for they now know who Zero is and the power of his Geass. As they threaten him, Kallen tries to defend him but they threaten her as well, accusing her of being under the spell of his Geass.

Kallen then asks Lelouch what does she means to him, implying she'd be ready to die if it's with him; Lelouch noticing Schneizel, understands there is no way out and as Kallen insist to have an answer he laughs sardonically while taking his mask, calling the Black Knights fools; To Kallen's shocked face Lelouch pretends she was his best pawn amongst all of them, for they were all pieces on his chess game. Kallen slowly turns around and let out a tear before whispering goodbye to Lelouch and begins to walk away from him as the firing squad prepares; Lelouch then whispers to her that she must live on, and as Kallen hears and turns back the Shinkirō suddenly lands, to save Lelouch. As Kallen yells at the Black Knights to wait before they fire again, they don't listen but Rolo freezes the perception of time for everyone with his Geass and escapes with Lelouch. This leads Kallen to realise it's the same thing which happened in Babel Tower. While Lelouch is on the run, Kallen tries to have the Black Knights come to their senses about how easily they discarded Zero after everything he did for them but they don't listen to her for they can't stand the idea of being used as pawns. After Rolo's death, while Lelouch is about to go and face the emperor, after one last call to Rivalz, he entrusts amnesiac C.C. to Kallen and professes his willingness to take down the emperor even if he has to die doing so. On her side, Kallen tearfully thinks to herself that Lelouch has to live for she wont be able to move on if she doesn't get her answer. A month later, when Lelouch is proclaimed emperor of the Holy Britannian Empire and Suzaku is announced as his Knight of Zero, Kallen and the rest of the Black Knights are visibly stunned.

Following Lelouch's declaration that Britannia will join the UFN, Kallen awaits for Lelouch to escort him to the meeting which will happen in Ashford, not before allowing the Black Knights to gun her down if she appears to be under the influence of Geass. As she is about to asks a question to Lelouch he greets her as if he didn't knew her and ask her if they can make a detour, for he is nervous. Kallen agrees and they leave. While they walk alongside the school Lelouch notices it's very nostalgic, leading Kallen to smile and to thank him for everything, for she would have died back in Shinjuku Ghetto if not for him. As they enter the Student council ballroom she explains how proud she felt of being needed by Zero and how distraught she was when she learnt he was Lelouch; as she tries to question him about his whereabouts with Suzaku we get a close up of Lelouch's sealed lips, clearly intent on staying silent. While they climb the stairs, Kallen mentions how Oghi told her Lelouch could make her brother's dreams come true before she stops and turn around asking him what he thinks of her and why he asked her to survive back in the Ikaruga; As he doesn't reacts she goes down and kisses him, eliciting a small surprised reaction before he kisses back. As they separate Kallen looks at him but he shows her a mannequin face. She eventually gives in, and sadly whispers her goodbye before telling him the meeting will happen in the gymnasium. As she leaves, once she is out of earshot, Lelouch sadly bids her farewell as well.

After that, when Lelouch takes the UFN leaders hostage during the reunion thanks to Suzaku's arrival in his new Lancelot Albion, Kallen takes out her Guren, insisting that she'll take Lelouch down personally, as she possesses the only Knightmare capable of fighting Suzaku, but she is held back by Li Xingqe who fears for the safety of the hostages.

After the Black Knights decide to side with Schneizel, Kallen, who is back in her old resistance outfit, has a talk with Gino who has decided to fight despite the fact it means going against Britannia, so he now thinks he can understands her feelings a little. During the final battle, Kallen is stationed in the front lines, noticing every move from Lelouch's Shinkiro. When the fight begins, she breaks away from the mainline to try and reach Lelouch but is called back. As Lelouch's defenses crumble Cecile propose to call back Suzaku who is on the opposite side of the battlefield but Lelouch refuses; Instead he choses to detonates the Mt. Fuji Sakuradite mines, hitting the Ikaruga and leading Kallen and Tamaki to get back to shield it from being destroyed by its crash landing. Once they know everyone inside is safe and sound, they all get back to battle.

As Lelouch and C.C. bids their farewell, Kallen's Guren suddenly crash in, as Kallen goes to threaten to kill Lelouch again, with teary eyes; She is stopped by C.C. who climbed very quickly into the pink Lancelot and both girls engage in a battle with various other Britannian forces; As Kallen accuses C.C. of not fighting for a country or for any ambition she mentions those who don't have reasons to fight should just stay on the side; C.C. tells her she has a reason, her promise; Kallen then asks her if that means she loves Lelouch to which C.C. replies she doesn't know but she wants to put an end to her accumulation of experiences. Kallen ironize about how human that sounds before eventually disabling C.C.'s Knightmare; C.C. gives her the win but Kallen doesn't care, bid her goodbye and leaves, as C.C. notices she finally cares anew about the idea of losing or winning.

Eventually Kallen is able to face off Suzaku in a very unplanned battle for it was possible only thanks to Gino who was able to disable the Damocles Shield enough to allow the Guren S.E.I.T.E.N. to enter the area; The two rivals then decide to fix their score and they engage in their final battle, with both talking over Lelouch and Nunnally's own dialogue, points of view changing and fighting to the bitter end. Eventually both Suzaku's shield and Kallen's radiation arm are out of energy and while Suzaku can't believe he isn't able to defeat her even with his live Geass command on, Kallen notices that with her superior specs she should be able to defeat him but she cant, leaving them both in admiration of the other pilot skills. Eventually Kallen manages to land a decisive blow on the Lancelot but her Guren shuts off and she loses consciousness as the Lancelot explodes. Gino catches the Guren as it falls and notices Kallen won.

A month after the final battle, Emperor Lelouch parades his prisoners for their final execution, with Kallen being one of them; When Zero appears and Kallen notices Lelouch is also there, she instantly understands what Lelouch was trying to do and yell from the top of her lungs for the action to stop; When Lelouch is stabbed she stares in disbelief as he falls down the altar; His last memories includes a few memories of Kallen with a notable pause on their kiss. When he is proclaimed dead, while Tohdoh stares in disbelief, A teary eyed Kallen acknowledges the new Zero as Zero.

Two months after Lelouch's death, Kallen prepares for school; As she puts her Guren key around her neck and has her natural hairstyle, while she is about to leave, she pauses in front of her picture wall and smiles upon seeing a picture of Lelouch at the center; She then begins to narrates the ending, speaking to Lelouch about how his plan actually worked, that everyone's energy is now focused on fighting hunger and poverty and that a human name was more fit to gather the hate of the world than a system like Damocles. She then notices he'd probably be laughing about how everything went according to his plan; She concludes by admitting everything isn't perfect but still ; We last see her as she bids goodbye to her mother from the small apartment they seem to have settled in before she runs to school.

Kallen's character poem "Extolling the brave chivalry of Youth" that came with the Code Geass Complete Best CD reveals she had fallen in love with Lelouch through her devotion to him and that even if it was lie, if he had told her he loved her, during their scene together at turn 22 she would have "followed him to hell". Knowing that she would do precisely that was the reason Lelouch remained silent, as he wanted Kallen to live on. She then declares it wasn't like him to be so kind and that she didn't fall in love with him just because of that kindness.

Code Geass: Oz the Reflection (Manga)
Following the Black Rebellion, Kallen had fled Japan with Urabe and had not yet reunited with C.C. after her battle with the Siegfried. The two had hidden in Gujarat a state in the northwest part of India. During this time, her Guren's destroyed Radiant Wave Surger arm had been replaced with that of a Gloucester. Orpheus had been given a mission by Rakshata to deliver specialized equipment for their Knightmares to use, including a replacement arm. However, the group is attacked by a Britannian Military group, the Blue Barons, and they fight off the group together.

Code Geass: Lancelot & Guren (Manga AU Timeline)
During the incident at the Special Administrative Zone, unknown to Kallen, she saved Benio Akagi from death.

Sometime later, Kallen returns to Japan and is given room and board at a harbor inn, and meets Benio Akagi. That same night, Benio warns Kallen that the owner of the inn plans to sell her out to Britannia. Thanking her, Kallen says she'll tie her up to make it look like she had nothing to do with it, though Benio says she would like to come with her. Though Kallen refuses, she tells Benio if she wants to help, that when the time comes, to head for Tokyo, though she doesn't elaborate on what she means. Kallen then fights off the Britannian Knightmares that come for her Guren hidden in the inn's warehouse.

Piloting Skills and Battle Prowess
Kallen is an extremely skilled Knightmare Frame pilot, rivaling the abilities of even the Knights of Rounds. She is acknowledged as the ace pilot of the Black Knights by enemies and allies alike. Her codename, "Q-1," references, in algebraic Chess notation, the Queen piece, the most powerful piece in chess. In Lelouch's assessment of the core members of the Black Knights, her "Combat Ability" score is 100 out of 100, matching that of Kyoshiro Tohdoh. It should also be noted that she was able to defeat Cornelia's personal squad, and later to the Knight of Ten, Luciano Bradley. She even could fight with the Knight of Zero, Suzaku Kururugi, on the same level even with his "live on" command activated. She was also able to pilot the Guren S.E.I.T.E.N. while it wasn't supposed to be able to be piloted by anyone. With the strong blasts and energy shots from the radiation arm of her Guren Mk-II, Kallen can take down almost any Knightmare Frame in a single attack should they allow her to make physical contact, apart of restraining their attacks with the strings of her Slash Harken projectiles and blocking their attacks with her fork knife by striking them down. Later models also have numerous secondary attack modes for mid- and long-range combat such as several improvements of its former weapons like more powerful explosions, while also gaining the Energy Wing System which gives her four wings which can act as shields, projectiles, and blades. Her Knightmare Frame is also incredibly fast, allowing her to fight on the same level as some of the most advanced Knightmare Frames in the series, and later also gaining the ability to fly at high speeds.

Outside of a Knightmare, Kallen displays superior fighting abilities at both armed and unarmed combat.

High Intelligence and Leadership
Kallen has shown high resourcefulness in battle, being able to see through her opponents' plans and usually takes advantage of their first mistakes or doubts in order to defeat them while making effective counterattacks. She also is apparently quite knowledgeable at academics since her grades in school are top of the class despite her frequent absences.

After passing more time at the Black Knights, Kallen has shown to be a good leader to her own squad's subordinates and even can be diplomatic to others while making plans at negotiations or tactics.

Lelouch vi Britannia
Her relationship with Lelouch becomes one of the main focuses in her character development, no doubt assisted by the complexities of their relationship and their numerous similarities while being one of the most complexes relationship of the show because of their various masks. While on one hand, Kallen initially disliked Lelouch Lamperouge due to his arrogant, seemingly-indifferent attitude to his surroundings and possibly due to the fact that everyone around them seem to think they're dating, leading even her to slap him on one occasion, on the other hand, Kallen holds a strong admiration and loyalty towards his alter-ego, Zero, due to his leadership and his beliefs in justice, which along with her impressive battle skills and her own ideals, gave her the position of his right-hand woman along with C.C. After it is revealed to her that Lelouch and Zero are one and the same, Kallen ends up believing Lelouch was just using her and her fellows comrades and eventually run away, but she eventually manage to step back, reforms the Black Knights with C.C. and Urabe, and begins to learn more about Lelouch thanks to her life with C.C. and their watching over mindwiped Lelouch's daily activities. After she eventually faced him off, she chose to believe in him again while separating both Zero and Lelouch, this leading to complicate situations where she would scold at Lelouch and not at Zero. With Lelouch showing off more of his good side, and with his flirtatiousness coming into play, Kallen eventually begins to soften up and begins to link the two personas, this event culminating when she manages to find him while he is depressed and has to slap him after he asks her for comfort "as a woman". The two grow closer after that, with Lelouch even asking her to come back to school with him when it's all over, but it's all cut short when she is captured; Even though it does elicit a very emotional reaction from Lelouch, while she'll spend her time in captivity learning more about him, Lelouch will lose more and more on his side, and when she'll be back at his side and will try to protect him against the Black Knights betrayal, he'll end up hurting her feelings in order to push her away so that she won't die with him, even though she is willing to.

Eventually, during their last face off Lelouch will remain completely silent and Kallen will kiss him before biding him goodbye. He'll do the same once she is out of earshot. The NT booklet of 2008 confirmed that their kiss was mutual and that Lelouch was hiding his feelings. After that, Kallen will take upon herself to defeat Lelouch because she will feel responsible for him going this far. She won't be able to reach him in the end but she'll understand Zero requiem and will help it by acknowledging the new Zero. Her Official Guidebook profile also says she understood Lelouch's feelings when Suzaku's sword pierced his sword as they came in the form of a quote from Lelouch himself : "I want you to live your own dreams, this is my little wish". In the Miraculous birthday picture drama, after Lelouch bids them goodbye Kallen proclaims she won't ever be able to forget him even if she wanted to. In picture drama 7.19, which is a scene Lelouch remembers after his depression in Turn 7, they have a very classical tsundere cliche scene with both being reluctant at being each other's date at a dance, the drama ending with Lelouch blushing upon seeing Kallen's dress fall down.

Suzaku Kururugi
Suzaku is Kallen's comrade in Ashford and rivals on the Battlefield ; While she doesn't learn directly he is the pilot of the Lancelot, which has been giving her trouble since Turn 2, she eventually does and gets quite distraught at the news, for she came to appreciate Suzaku at school and seems to appreciate him as a comrade. Even though she'll place her duty above everything and will try to kill him, both on and off the battlefield. Eventually when Suzaku will learn of her identity they'll share their reasons to fight and their different views and ultimately, Suzaku will chose to not denounce her and to try to keep on convincing of her path being the wrong one outside the battlefield. After Euphemia's death, Suzaku will become more ruthless, even with Kallen, being even more prepared to kill her if necessary; During Zero's revelation he will insist on the fact Zero was using both her and the Japanese, adding even more confusion in Kallen's head.

In R2 they'll be enemies to the bitter end, and it will get even worse after Suzaku tries to drug her in order to get answers; Kallen will beat him up and will claim she hates him. She'll get even more upset when Lelouch will team up with Suzaku for she has no trust in him ; Eventually they'll have a final face off and Kallen will admit she always believed Suzaku actually wanted the same thing as her ultimately but she now thinks she was wrong. In the end, Kallen will acknowledge Suzaku as the new Zero.

C.C.
Kallen and C.C. have a very evolving relationship; While at first, Kallen was suspicious of C.C., jealous even, because C.C. knew who Zero was, we got to see their relationship unfold in various CD Drama or picture drama, especially when they had to live together, as big and little sister, in between both seasons; Thanks to C.C. Kallen managed to learn more about Lelouch, C.C. obviously enjoying teasing her about her temper when it came to Lelouch's secret, and Kallen not being the last to try and tease her back, even nicknaming her "pizza girl" or mocking her about her figure in Beautiful Record of the Rebellion.

Above all the teasing we got to see C.C. relieved when Lelouch chose to go after Kallen against good sense, so she obviously cares a great deal about the younger girl. Ultimately they won't have much moment to share, their final encounter known being when they will fight during the final battle before Kallen disables her Knightmare and bid her goodbye.

Benio Akagi (In Lancelot and Guren Manga)
According to Kallen, she says that if she had a younger sister, she imagines their relationship would be like the one between her and Benio. Noticing her talent during her training, she stops Kagari from ending the mock battle when it seems she is on the losing end to Tamaki. When Benio volunteers for the Zero Squad, Kallen gives Benio her old Knightmare, now the Burai Custom. When Benio is overcome due to the emotions she feels after taking her first kill on the battlefield, Kallen is the one to help her and tells her to hold on to those feelings, because she isn't some mindless machine. After learning the truth of what Lelouch did to Benio along with Kagari, she knew it would be the best for the two despite looking at Benio with a sad face since she no longer remembers her.

Code Geass: Lelouch of the Re;surrection Timeline
Kallen is reduced from a main character to a supportive character in the alternate movie version; Most of her scenes with Lelouch are cut out, she barely appears in his final flashback, and she shares the epilogue with the surviving Shirley. Her role as Zero's protector during the Black Knights betrayal is also undermined with various of her lines being now said by Oghi or Tamaki. She also doesn't have any picture of Lelouch's face anymore as her picture board only bears a picture of Lelouch's back.

During her first appearance in the movie Lelouch of the Re;surrection, Kallen is seen with Lloyd and Sayoko while they are being pursued by soldiers from the Kingdom of Zilkhstan, Kallen was shocked to see Lelouch alive, she even cried when mindless Lelouch came to try and comfort her. When Lelouch is back, she gives him a hug and notices he is different. Later on, in the movie it was revealed Schneizel sent Cornelia li Britannia with a small number of troops to monitor the region while sending Kallen Stadtfeld, Lloyd Asplund, and Sayoko Shinozaki to infiltrate Zilkhstan for information. Together alongside Lelouch and C.C she was able to help rescue Nunnally.

Lost Colors
In the video game spin-off, Kallen is one of the potential love interests. She asks to meet Rai in a hot spring. The rest of the student council comes in while they are talking, resulting in Kallen trying to explain the misunderstanding. Kallen eventually walks out.

In the Black Knights path, if Rai stops Princess Euphemia from following through with Lelouch's accidental Geass command (an alternate version to episode 22-23), Kallen shows a great deal of gratitude toward Rai for saving the Japanese. Afterward, Rai and Kallen continue to be faithful members of the Black Knights. It is even hinted that she likes Rai. Further more members of the student council and the black knights even noted how close both Rai and Kallen are and just assumed that both of them are dating and are poorly hiding it.

Code Geass: The Manga
The manga differs from the real series focusing on the Black Knights activities, in the manga Kallen is not present during C.C's appearance. Lelouch's first meeting with her is also different as she bumps into him at school. She is in love with Zero but despises Lelouch.

Kallen protests at the school rather than at the settlement. She is also apparently Zero's only soldier as only she helps him, such as when they rescue Suzaku. She shares the same relationship with Lelouch in the anime with her admiration for Zero and dislikes for Lelouch. It also hinted that she has a crush on Zero due to her extreme reaction when she thought Zero had come to save her. Also, she was not with Ohgi and the other resistance members until the Black Knights are formed. She later finds out that Zero is Lelouch when he runs up to meet up with him and the other Black Knights at the Government Bureau to take over it only to be stopped by Suzaku and similar to the anime, she abandons him learning everything from Suzaku.

In the second part of the storyline, she helps Lelouch regain his memories of C.C. and Geass with the help of C.C as a food cart worker instead of a bunny girl. She meets Lelouch at Ashford Halloween party not the second annual school festival about her loyalty as well as helping C.C escape due to obsession with pizza. She does not get captured and is with Zero the whole time until the betrayal. She kisses Lelouch during Britannia's entrance to UFN. After Zero Requiem, she narrates to him about how the world has changed.

Nightmare of Nunnally
Kallen and the other Resistance members took advantage of the arrival of Nunnally's Mark Nemo Knightmare Frame to make their escape from Britannian forces pursuing them. When Kallen escapes from the rooftops after she was taken hostage with the other student council members in a hotel at Lake Kawaguchi, she witnesses the arrival of the Mark Nemo.

Suzaku of the Counterattack
In the manga spin-off, Kallen becomes a member of the Black Knights after Zero forms the organization but has doubts about his methods after a Black Knight faction had gone renegade and orchestrated an attack, taking the lives of nearby civilians, including Lenard Lubie.

When Zero is planning to attack the Britannian Art Gallery with the goal of assassinating the Emperor who has arrived there, Kallen confronted him about whether it would be a trap and also commented that she would still follow him. Admiring her answer and loyalty, Lelouch placed a Geass command on her that if anything would happen to him then she would lead the Black Knights. When the Black Knights took the Art Gallery hostage, she is confronted by Suzaku and was surprised that she's not only a member but a half Britannian-Japanese right after he left to stop Zero from killing the Emperor. After Lelouch was captured and accused of killing the Emperor, Kallen assumes leadership of the Black Knights as the new Zero and later leads the remaining Black Knight members to begin an assault on the Governor Building of Area 11, unaware that Lelouch is freed by Suzaku and are both planning to stop Schneizel.

Five years later, a 22-year-old Kallen is seen walking on the street and still a member of the Black Knights and in contact, but while she was passing by, she suddenly saw someone who looks like a 17-year-old Suzaku, which she thinks she's imagined it.

Nunnally in Wonderland
In Code Geass: Nunnally in Wonderland, Kallen plays the role of the March Hare. While Nunnally is at the White Rabbit's (Anya's) house, Kallen storms in, demanding to know who is causing all of the noise, which was caused by the Cook (Nina). During this time, she ends up fighting the White Rabbit to determine who should be the only rabbit in the forest, with both of them using carrot-like objects in a fashion similar to the weapons used by their respective Knightmares. Their fight ends up causing Nunnally to leave the house, much to Lelouch's anger, since he wanted them to be more hospitable to Nunnally. After Nunnally leaves, the March Hare, the White Rabbit, the Cook, the Duchess (Milly), and the Dormouse (Rivalz) realize that they are missing the Mad Hatter.

Super Robot Wars Z2
Kallen makes her debut as the Red Devil of the Elevens and fights Chirico from Armored Troopers Votoms and loses. Her manager Kolin betrays her and she and Chirico team up to fight him. She ends up in an arm-wrestling match with Kamina from Gurren Lagann since they both have mechas named Gurren. Ester, Crowe's disciple, idolized her and formed a friendship with her. She helps Lelouch when Heero and Wufei try to kill him.

Granblue Fantasy
Article in Granblue Fantasy Wiki.

SINoALICE
Kallen/Crusher in SINoALICE

Shadowverse
Kallen is an optional leader for Bloodcraft decks.

Quotes
"Extolling the Brave Chivalry of Youth* Kallen's regret Message from the CD complete best Until I met you, I was only merely plastered with thorns.

I wanted to change this truth.

''I seethingly and recklessly acted. But then, I didn’t believe that anything would come out of it. ''

When my brother was gone,

I heard the sound of the heavy doors closing behind me.

''I cannot allow it. I will fight to the bitter end. I decided that I would not go back.''

Then, someday, I would have died like my brother.

Until the very end, Kouzuki Kallen would not abide by authority.

That bit of willpower I was carrying with me, it slipped away from me, and I can feel it faintly.

''At that moment, I envisioned you as the star at the break of dawn, inviting me. ''

If I would think that this is for you, my body would feel light.

Whatever struggles there were, the pain would go away.

I would be the first to come rushing to your battlefield,

raging like a lioness, crushing your enemies.

''I would stand being muddied so that I could create a path for you. ''

Looking back, it's mysterious.

Even though I should have loathed and rebelled against Britannia's tyranny.

''Without knowing it, I held personal devotion only for you. ''

Lelouch, that parting kiss,

even if it was a lie, if you had said, "I love you," **

I would even follow you to hell.

You knew that, didn't you?

It's not like you.

You're good at manipulating people just by your words.

Really, it's not like you to be kind.

Is that why you told me to 'live on'?

I fell in love with you*** not just because of that kindness. ''* Extolling the Chivalry of Youth (Yuukyou Seisehunka) is the title of the 1st ending.** Kallen uses the word 'aishiteru' here. It is a word that carries strong weight in Japanese and is not simply used to express love. You may say 'suki' and mean love, but 'aishiteru' is used between two intimate lovers.*** The love here is 'suki ni naru' ''


 * 1) "It's not bad to just have a little fun once in a while"
 * 2) I will make a world where you and I can live a normal life again, I promise you !
 * 3) "That's why I hate Britannians!"
 * 4) (To Zero) I'm doing it for Justice. Today again, I fight because I believe that it's the rightful path to take. That's why I kill people.
 * 5) (To Zero) Let's move on together. I will move ahead with you.
 * 6) (To Suzaku Kururugi)"Honorary Britannian ? The amazing Knight of the third princess ?", Ah ! The last samurai, Kururugi Genbu, is in tears !
 * 7) (To Suzaku Kururugi) I will show that i can change this unfair world. Otherwise, if I don't my brother won't be able to rest in peace. This is why I will fight !
 * 8) (To Suzaku Kururugi)"Then tell me. What was the point of my brother's life? Who gets to decide whether what's right or wrong?"
 * 9) "You fellas know full well what this badass mother can do!"
 * 10) (To Lelouch vi Britannia) I want to believe ...even if it meant becoming a slave. But I'll believe in Zero, not in you, Lelouch.
 * 11) The face of the older brother, and the mask of Zero, which one is the real Lelouch ?
 * 12) (To Gino Weinberg)"Zero is coming !?"
 * 13) "Please answer me Lelouch, what am I to you ? If it's with you, I could..."
 * 14) "Sayonara, Lelouch."

Etymology

 * The name Kallen has many meanings:
 * In Irish, it means "mighty warrior".
 * "Kallen" (American name) meaning "Pure".
 * "Karen" (Japanese name) meaning "カレン・シュタットフィールド", which means "beautiful as a lotus flower".
 * Kallen's Japanese surname Kōzuki means "crimson, deep red" (紅) (kō) and "moon" (月) (tsuki/zuki).

Trivia

 * Kallen's plushie's name is "Tabatacchi"
 * In Lelouch vi Britannia's assessment of the core members of the Black Knights, Kallen has the highest Loyalty with 100 of a 100.
 * "Q-1", the codename given to Kallen by Zero is in reference to the queen, the most powerful piece in the game of chess. A fitting name as Kallen is the Ace of the Black Knights and his closest ally aside from C.C.
 * In an interview reported by the anime magazine Newtype USA, Seiyuu Ami Koshimizu talked about the difficulty of voicing Kallen because of the double life that her character had. Certain aspects of Kallen's character such as her girlish naivete and competitiveness made it easy for the voice actress to relate, even to the point of admitting that in some ways they act very much the same.
 * As a running gag, Kallen ends up naked or immodestly dressed in front of other people on numerous occasions: Lelouch sees her naked after she pulls back a shower curtain in surprise in the third episode, Suzaku Kururugi sees her bathing under a waterfall when they are stranded on Kaminejima Island, she is forced to dress as a Playboy Bunny at the start of the second season, and she walks in on a meeting between C.C. and the Chinese ambassadors wearing only a towel when attempting to complain about the previous situation to C.C. Another possible running gag is her relationship with Lelouch as they are set up in scenes where they almost kiss but always get interrupted,
 * Kallen Kōzuki has quite the number of similarities with Domon Kasshu from the Sunrise anime Mobile Fighter G Gundam, such as hairstyle, personality, penchant for skintight piloting wear, their respective mecha having the same finishing moves, to the point where fans often joke about Domon being her real Japanese father due to the fact his love interest, ‎Rain Mikamura, has the same seiyuu as Kallen's mother (Yuri Amano).
 * Aki Izayoi from Yu-Gi-Oh! 5D's bears a striking resemblance to Kallen; both sport a crimson theme as well as a similar hairstyle. Personality-wise they are not exact, but similar since they try to isolate themselves from the present society during the story and are hostile to the people they perceive as enemies. They also have romantic feelings for the main protagonists of their respective series.
 * In Spice and Wolf, Holo, the main heroine of the series, was voiced by Ami Koshimizu who also voiced Kallen Kozuki. The main lead of this anime, Kraft Lawrence, was voiced by Jun Fukuyama who also voiced Lelouch Lamperouge/Lelouch vi Britannia/Zero.
 * It is notable that the anime was created after both actors, Jun Fukuyama and Ami Koshimizu, won the 1st Seiyu Awards for their respective roles in Code Geass - Lelouch of the Rebellion.
 * In Super Robot Wars X during a DLC mission, after the Zero Requiem was over, she admits that she felt left out, and knowing that so many people knew about the plan, she felt that they didn’t believe in her. She even went as far as to tell Suzaku that they better not do it to her again.
 * Karen Strassman, Kallen's English voice actor, played alongside fellow Code Geass voice actors Johnny Young Bosch and Yuri Lowenthal, the voices of Lelouch and Suzaku respectively, in the video game Persona 4. Strassman played the protagonist's young cousin, Nanako Dojima, as well the true antagonist of the game, Izanami. Interestingly, the game released only 74 days after the English broadcast of the very first episode.

Gallery
de: Kallen_Kōzuki