Yuu is the overarching antagonist of the anime Guilty Crown. He helps Mana Ouma to develop her powers.
She was voiced by Yuka Nishigaki in the Japanese version and Leah Clark (who also voiced Himiko Toga in My Hero Academia, Miss Doublefinger in One Piece, Muru Muru in Future Diary and Queen Bee in Panty and Stocking with Garterbelt) in the English version.
Appearance
Yuu, though a male, has very female-like delicate features. He has fair hair that reach to the back of his neck and bangs that cover the mid of his forehead. He has sensitive, light blue eyes and a slim, short body. He usually wears a black shirt or black vest over black jeans or trousers with a pair of plain black shoes. Though he is not affiliated to any research labs, he is usually seen wearing a lab coat.
While guiding Mana about her powers for the first time, he was seen wearing black boots with golden-orange buttons on its sides.
Personality
Although he comes off as very polite, Yuu is a self-concerned sociopathic maniac. His sole objective is to guide Mana so that she can develop her objective of living a queenly life with her soulmate while ruling the crystallized world. In order to help Mana, he built an association called Da'ath in which he employed people who could help him. He is cruel and doesn't care about his own people, abusing and sacrificing them. Yuu is extremely devoted to his cause.
Biography
Past
Yuu was seen for a split second in the OVA, smirking at his will-be association members, Scrooge and Carol when their powers are revealed.
He is seen in flashback of Shu Ouma's past, where he taught Mana Ouma to practice her powers and informed her father and Shuuichiro Keido, the scientists working on the same virus that Mana inhabited, about Mana's powers, needs and wishes.
Guilty Crown
Yuu is first seen kidnapping Inori in order to revive Mana out of her. He is quickly chased by Shu, whom he dismisses by saying that he did not need people who didn't remember their past. Shortly later, he is seen performing a sacrifice along with Shuuichiro Keido so as to bring Mana to life.
A little while later, Yuu is seen defending Gai Tsutsugami as Inori is used to revive Mana for the second time. He stops Shu so that he can't save Inori, and pauses between the fight to ask Shu if he would accept Mana as his soulmate and love her forever to which Shu replies that he would not and admits that he loves Inori more than Mana. Yuu laughs maniacally at Shu and tells him that he was indeed not worth being Mana's Adam as he still preferred a fake like Inori over the goddess Mana.
He then proceeds to try and kill Shu, which he fails at, and Shu gets past him.