Rengoku no Cartagra

At Seirei Academy, a prestigious institution, a series of enigmatic and ominous demonic rituals have been taking place, shrouding the school in an aura of mystery. The arrival of transfer student Yuriya Yuuki sparks suspicion among his peers, who begin to wonder about his involvement in these eerie ceremonies. One evening, from his dormitory window, Yuriya catches a glimpse of a girl wandering outside, and his curiosity gets the better of him. He follows her, and upon exiting the building, he stumbles upon an ancient tome that holds the power to summon the demon Belial. The demon, with an air of sophistication, invites Yuriya to enter into a contract with him, binding their fates together in a delicate dance of power and responsibility.