A long time ago, the Earth was ruled by demons. The demons constantly fought each other for survival, but soon found themselves fighting a new race of beings: the first humans. The demons then became imprisoned in ice after a great cataclysm. They would remain there until the ice melted, after which it was said Satan would rise and lead them in Armageddon.<br /><br />Akira Fudo's best friend, Ryo Asuka, introduces him to this schocking truth, and asks for his help in his plan to save humanity: to borrow a devil's power and create a hybrid, a devilman who can protect humans from demons.