A strange group of cultists with the ability to transform into demons have begun to gather a black mass in hopes of reviving an ancient devil lord known as Dante. Ryō Utsugi, a high school student, begins suffering strange dreams and premonitions. Soon after, Ryō's sister, Saori, is kidnapped by these cultists for use in their sacrificial ceremony in hopes of reawakening Dante. Ryō's premonitions guide him to the ceremony, and just before Saori is to be killed, the cultist's ceremony is disrupted by a force of holy men. This happens just in time for Ryō to save his sister from her fate.