V.V.

V.V. (ヴイ・ツー, Vui Tsū can be pronounced V2) is a mysterious boy with blond hair longer than his body. He is the twin brother of Charles zi Britannia, but looks much younger because he has gained the power of immortality through a Geass contract like C.C. He can grant Geass contracts like her, having given both his brother and Rolo Lamperouge their Geass abilities, among others in the Geass Directorate. He succeeds C.C. in becoming leader of the Geass Directorate, a secret organization that studies and produces Geass users. He is one of the main antagonists in the series

Overview
He is the older twin brother of Charles zi Britannia, but as has become immortal at the early age of 10, there is an seemingly immense age difference between them (his exact age is unknown). C.C. refers to V.V. as Charles' first ally and has indeed been actively supporting him in his childhood years. Charles and V.V. childhood years were marred by an internal feud in the Imperial Family called the Emblem of Blood. This period filled with deception and assassination resulting in the deaths of various members of the royal court including their mother. This event convinced the two to create a Geass contract to create a world without lies and to do so, they intended to destroy the "Gods". Several years later, Marianne Vi Britannia and C.C. joined in their venture as well.

First season
During the time of both the invasion and Black Rebellion, V.V remained behind the scenes hiding among the highest ranks of the Britannian Royal Family. He and Charles were starting expeditions to find Thought Elevators across the planet. He was seen briefly transporting Lelouch, Suzaku, Kallen, and Euphemia to Kamine Island in episode 18. V.V. appeared again to Suzaku Kururugi to tell him about Geass and that Zero was responsible for Euphemia Li Britannia's murder. After that he kidnapped Nunnally Vi Britannia and once again disappeared into the Sword of Akasha using a thought elevator, resulting in Lelouch's sudden abandonment of the Black Knights' chain of command.

Second season
V.V was more active during the Black Knights' second uprising. He leads the Geass Directorate, a secret organization that studies and produces Geass users, as with Jeremiah Gottwald's Geass Canceler. When Cornelia comes to stop the Geass research, she tries to kill V.V by throwing a knife at him (assuming him to be an individual with a Geass power). He shocks her by pulling the knife out, despite that it was burried deep in his forehead, and takes her prisoner. The research would stop as the Black Knights invaded the Order killing all the researchers, civilians, and subjects, as well eliminating all traces of their research. In the ensuing chaos, he pilots the Siegfried during Lelouch's assault on the Geass Directorate. Though he manages to hold his own at first, he is caught off-guard by Cornelia, who has hotwired a damaged Akatsuki with an array of weapons. She and Lelouch destroy the Siegfried together. He manages to reach the Twilight Door to the Thought Elevator in the complex only to have his code taken by Charles, leading to his death and granting the Emperor immortality.

In a flashback, it is revealed that V.V. was the one who assassinated Marianne, having done so out of jealousy. He lies about this to Charles, breaking his promise of mutual honesty between him and Charles when he lied of his part in Marianne's death.