Nora, an unruly demon, has defied his superiors one too many times. For the sake of his ""education,"" Nora is sent to live among mortals and enters a bond of servitude with cool-as-ice star student Kazuma Magari. Kazuma is about to learn the ways of the underworld...and Nora will learn more from the ""real world"" than he ever thought possible!
Nora's presence on Earth has made him a target for renegade demons. But when he uses magic to fight them, it takes a toll on Kazuma's body! The Dark Liege sends Kazuma a ring to counteract this effect, but what Kazuma really needs is information on the legend of Cerberus, Nora's true form. Too bad the one with the info is one of the demons he's fighting!