Koyoi Bessho

Koyoi Bessho (別所 小宵 Bessho Koyoi) is one of the main characters in the show. She is a middle school student and the sister of Yoshihiko. For a while when Misao started hanging around, she, along with Nao Chikura, stops walking home with Ayumi. Since her brother likes Misaki, a popular and attractive girl, she regards her as a "Final Boss" that she must defeat. She also quotes that Misaki's chest is a "truly evil power."

Trivia

 * Koyoi has an open brother complex with Yoshihiko (Koyoi's brother), which stresses him a lot.