Yumi Ookura

A female scumbag obsessed with idols, to the point of being extremely perverted. She develops a particular fondness for Mizusawa Haruka when they audition to be in an idol group, STH24, specifically created for loser girls. [Spoiler] She cuts her hair and wears makeup for the idol show, as well, she stops Masahiko from killing Haruka. [/Spoiler]