The school Trinity was founded for people to hone their skills and to promote cooperation between the demon, god and dragon races to prevent another war. Despised for coming from a race that once started a war in the past, he came to gain strength so he can protect others. He became close to three powerful girls: Vell of the demon world, Note of the god world and Uluru of the dragon world. One day, Uluru met a suspicious robed person and fought them off. A few days later, a girl from the demon world named Von transfers into Trinity. Uluru’s maid servant Opera has a sense of uneasiness from her and warns Uluru. No one realizes that Uluru will soon confront her own past.