Irina, the third daughter of the three Nemoto sisters, is a plain, college science student who wears a white coat and glasses at school. It seems that things are going well with her boyfriend Soga. One day, while Irina is studying ancient Japanese history, she discovers a system in which women share a man sexually.

Cast:Akika Kitagawa, Anna Tomo, Kyôko Kazama, Mutsuo Yoshioka, Seiji Nakamitsu, Naohiro Hirakawa,

Genre:Comedy,

country:Japan,

Production:Tantan-Sha Company, Okura Pictures,