Yuu Otosaka

Yuu Otosaka is the main protagonist of the story and a first-year transfer student at Hoshinoumi Academy. He has the ability to temporarily possess a person for 5 seconds. However, it is later revealed that his actual ability is stealing the abilities of the ability-user he possesses. Towards the end of the series, he becomes widely known (and feared) as the One-Eyed Grim Reaper. He is also the younger brother of Shunsuke Otosaka, and the older brother of Ayumi Otosaka.

Yuu has dark brown hair, and maroon eyes, various outfits throughout the series but is mostly seen in his Hoshinoumi uniform, which consists of a black jacket and a white under-shirt with a dark blue shirt underneath, black pants, and brown shoes. He is also considered handsome by his peers and friends.

After his sister death, Ayumi, Yuu goes through severe depression and instability. He goes as far as locking himself in his room for days, doing nothing but eating instant noodles and watching TV. After escaping Hoshinoumi, Yuu's mental state continues to deteriorate, and he begins picking fights with gang members, finding joy in having them beat each other up while he possess them and injures them. He is also shown to be borderline sadistic, as he laughs with glee after stabbing one such gangster in the leg with a wooden skewer. He continues to go in a downward spiral and even reaches a point where he is about to use drugs.