Kitakubu (literally, go-home club) is Japanese slang for kids who go home instead of joining clubs, sports, or other afterschool activities. In one high school, there is a real Kitakubu of girls who do whatever they like. The president is a free spirit named Sakura, while Botan is the combative heir to a school of ancient martial arts. Claire happens to be the daughter of the head of the powerful Kokonoe conglomerate. Natsuki joins the club at the invitation of another freshman, Karin, but she is unprepared for the hijinks there.