The main protagonist in the fourth (technically fifth) Bishoujo Mangekyou, Tsumi to Batsu no Shoujo (Girl of Sin & Punishment).
Yuuma, who has skipped classes due to hospitalization is ordered by his father, Kannagi Reijirou, to study in an all-girls school. His reason for being hospitalized is due to his abusive father. He's also a huge siscon and is not great at socializing. His twin sister is Yuuri.
