Takuya Oki

Oki was jealous of Hikaru's loving family because he was abused by his alcoholic parents. But when one day he sees Hikaru wander onto a bus by himself, he goes after him out of worry that he can't explain. Later, Oki's mother leaves his home and his father dies of liver damage, causing Oki to be sent to an orphanage, where he is abused by the other kids and possibly some of the staff.