Sado Tarou suffers from sexual masochism; he experiences sexual pleasure from pain. He falls in love with a certain girl, Shihori, but decides he cannot pursue her with his condition. His best friend, Tatsukichi Hayama, tells him to visit the Voluntary Club, a place that grants students' wishes, for a cure. At the club, he finds Isurugi Mio, a girl who thinks she is a god. She pretends to be nice but as soon as Tarou tries to leave, she turns into an evil monster telling him that she was being patient. He also sees Arashiko Yuno, whom he apparently has known before in middle school, the girl who was actually responsible for his masochism. Later, Mio decides to continue his treatment by giving Tarou so much pain, his mind will no longer feel any pleasure. She injures him so he must stay in the infirmary where Yuno looks after him.
白球が頬をかすめる。その熱は頬を瞬間的に上気させ、誰が見てもわかるくらいに赤く染まった。砂戸太郎は物怖じすることなく、むしろ興奮を伴い次の球を待つ。不敵に微笑む小柄な美少女の金属バットが火を噴いた。
Taro se une al club de voluntariado para curarse de su masoquismo y confesar su amor a Shihori una chica de la que solo sabe el nombre, ahí conoce a Mio quien le ayudara con métodos poco ortodoxos.