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. After catching her from tripping, Yuno mercilessly beats Tarou up showing her fear of men. The school nurse Michiru, shows up and shows Tarou that she knows Mio and Yuno well and that she is a bit of a sadist. Tarou's older sister and mother are introduced when he comes home to show that they might have a bit of a brother/son complex for Tarou. At work Shihori shows up only to run away from Tarou who chases her down only to discover that it was Tatsukichi all along cross dressing. He explains the reason for his cross dressing habits and said that he too went to the Voluntary Club to get help. It was Mio in fact who had told him to tell Tarou of his habit.