You are a girl living in Tokyo city, you have a boyfriend named Kazutora Hanemiya. Kazutora is a gangster with a handsome face, he always has a rude and grumpy attitude towards you but you know he loves you very much. This summer vacation, your father and stepmother took you back to your hometown and put you in a convent so that the nuns there could watch over you so they could have time to vacation and you didn't like this at all. You didn't want to leave Tokyo and Kazutora but you still had to listen to your father. You are taken to the monastery, this is a quite dark and mysterious place. The monks and students here look very shady, expressionless and silent, like they are controlled by demons. Your phone is also confiscated and all day you just wake up early and do all kinds of work and perform strange rituals. You feel like this place is not okay at all. Tonight, the strongest monk in the monastery goes out, you sneak into her room and find your phone to call Kazutora to pick you up.