Milly Ashford (ミレイ・アッシュフォード, Mirei Asshufōdo), 18 years old (19 in R2), is the granddaughter of the Ashford Academy superintendent, Ruben K. Ashford, and president of the Student Council. She is voiced by Sayaka Ohara (Japanese) and by Julie Ann Taylor (English).
Milly is Lelouch's friend and classmate at Ashford Academy. She has a curious and playful personality; for example, she often gently teases her friends about random things; such as Shirley's inability to express her true feelings for Lelouch openly. Milly is eager to discover Lelouch's secrets; often using over-the-top methods in attempting to find them - so much as to rally the entire school into chasing after Arthur when she suspects that the cat is holding something precious to him.
Milly is secretly in love with Lelouch, but realizes the need to restore her family's status by marrying a noble. She is aware of Lelouch's identity as a former prince of Britannia, since her family were close supporters of his mother, Empress Marianne. This relationship however, would lead to the family's nobility status being stripped.
The Ashfords, wanting to restore their former glory, have two options in doing so; either reinstate Lelouch and Nunnally back into the royal family, or to arrange a marriage with a noble. The Ashfords opt for the latter, and arrange a marriage interview for Milly, with Earl Lloyd Asplund; much to the grief of Rivalz Cardemonde, who carries an unrequited love for her.
After the events of season one, Milly remains a student at the academy because she failed her examinations, although it is noted that she did so on purpose, so as to remain on campus with her friends. She was delighted to hear that Suzaku Kururugi had returned to Ashford Academy and in celebration, threw a large party for him. While Suzaku began preparations on the MR-1 that he was supposed to operate; he mentions to Milly that Nina was doing well; she had apparently presented a thesis of hers, at a science academy recently; to which Milly wondered, if she had yet perfected the Ganymede. During the conversation, Suzaku also makes a passing mention about Lloyd Asplund. While on the subject, Milly asks if Lloyd had mentioned anything about her; since their wedding was postponed as a result of having to repeat school. Suzaku replies that he hasn't heard anything from him, and further added on a personal note, that there were 'so many things wrong with him as a human being'.
Sometime later, Milly attends the wedding banquet in the Chinese Federation between First Prince Odysseus and Empress Tianzi. While there, Milly asks Lloyd if she's still his fiancee’, to which he believes she is, since they never actually called off the engagement. Just then, Second Prince Schneizel arrives at the reception, with Nina Einstein at his side.
Wanting to catch up with her old friend, Milly goes to speak with Nina in private; during their conversation, Nina mentions Milly's upcoming graduation from Ashford Academy. Milly confirms her intent to finish school and expresses her happiness towards Nina's new life; telling her that if she needs any advice, she'll be there to support her. Upon hearing this, Nina slowly becomes irritated and upset. Milly attempts to console Nina, but it only results in a harsh response. Despite this, Milly still sees Nina as a friend.
After returning to Ashford Academy, Milly promotes her final day as student council president by declaring 'Cupid Day'. During the event, Milly offers to increase the funding of any school club that is successful in bringing Lelouch's hat to her. Various groups try to catch him, but their attempts are unsuccessful. After earning enough credits to graduate from Ashford Academy, Milly breaks off her engagement with Lloyd and becomes a reporter for KT-TV, a local television news.
She is seen attending the funeral service of Shirley Fenette, after her death had been declared a suicide. At one point, she asks if anyone has seen Lelouch. Rivalz Cardemonde, who was also in attendance, only shook his head in response.
Later on, Milly presents a report on the estimated military strength of the UFN, during it's formation ceremony; which was now large enough to rival the combined forces of Britannia's own military. Soon afterwards, the UFN announces it's first resolution; the liberation of Japan, resulting in a declaration of war between the UFN and the Holy Britannian Empire. The second battle of the Tokyo Settlement soon gets underway, with Zero activating several trains equipped with Gefjun Disturbers, in order to give the Black Knights an upperhand; knocking out various parts of the Tokyo Settlement; including the TV station, where Milly was giving a report on the situation. As the settlement soon becomes too dangerous to remain in, Milly and the TV crew are forced to evacuate from the area. Ultimately, they escape the detonation of the F.L.E.I.J.A. warhead that was fired from Suzaku's Lancelot Conquista.
Eventually, Milly arrives at Ashford Academy; which is being used as a relief shelter. While waiting in the school gymnasium, she is reunited with Rivalz. Milly continues her work as a reporter, with Ashford Academy acting as a temporary studio for KT Television.
After succeeding his father as the 99th Emperor of the Holy Britannian Empire; Lelouch made drastic changes to Britannia's previously established policies; notably, the abolishing of the area system and the nobility structure; effectively ending the Ashford family's quest to regain their former social status. Emperor Lelouch later announces that the Holy Britannian Empire will join the United Federation of Nations; declaring Japan as the site for the negotiations, with Ashford Academy as the location of the meeting grounds.
Milly is sent to cover the Emperor's arrival; during which, she comments to herself if it really is Lelouch that she's seeing, only to correct herself immediately after remembering that she was live on air. During the meeting, the UFN delegates realize that Britannia's large population would give it a supermajority vote; essentially giving Lelouch control of the organization. When they try to get him to limit his vote, Emperor Lelouch responds by taking the delegates hostage with Suzaku in the Lancelot Albion, stunning everyone who was watching the meeting unfold; including Milly, who expressed her surprise at Lelouch's actions.
She stays at Ashford Academy with Rivalz, during the final battle over Mt. Fuji. While in the student council room, Milly mentions to Rivalz how amazing their friends are. Initially, he felt that she was being sarcastic; blaming himself for allowing Nina to be taken away earlier. Reassuring him, Milly tells Rivalz that he did his best.
With the battle over Mt. Fuji unfolding, the remaining citizens of the Tokyo Settlement start to evacuate. Out of curiosity, Milly asks Rivalz if he was planning on leaving as well. He tells her, that there isn't anywhere else for him to go to; and that all he really wanted, was to hangout with his friends everyday. They later both witness the assassination of Emperor Lelouch at the hands of Suzaku Kururugi, who was disguised as Zero. Although neither were aware of the fact that Lelouch had planned for the entire event to occur.
In the epilogue, Milly is found reporting on the meeting between Nunnally vi Britannia, who is now working as an important diplomatic figure, and newly-elected Prime Minister Ohgi. She is last seen among the guests in Ohgi and Viletta's wedding photo.
- In the second picture drama special included on the DVD release, it states that Milly and Nina's grandfathers both worked on the Ganymede Knightmare Frame.
- In one of the Code Geass magazines, Milly is ranked number one in breast size, of all the female characters in season one.