One day after school, the half-youmu boy, Kanbara Akihito, meets a girl who looks as though she is about to jump off the roof at any second. Her name is Kuriyama Mirai, and she is the last surviving member of a clan that has a blood curse that is unique even among the Under World Warriors.
An unchanging room. An unchanging lifestyle. An unchanging world. That was how his days were supposed to be. Yet, the moment that girl survivor met the half-youmu boy, his world changed completely.
