Mayami Tanaka

Manabu's younger sister. Mayami is revealed to be a masochist, and ever since Reina accidentally hit her, Mayami began expressing affection for Reina and wishes Reina to become her "honored sister". Though she is very cute and popular with boys, she thinks that men who hit women are scum, and will only like Reina's punches. Her personality is very blunt, optimistic, and bouncy, making her opposite of Manabu. (Source: Yandere Kanojo Wiki)