Despite possessing the power to destroy humans, elves, and even gods, the tyrannical demon king Anos is tired of the endless struggle and dreams of reincarnation in a peaceful world. However, two thousand years later, what he is greeted with after reincarnation is his descendants who have become too weak to adjust to peaceful life, and various magics that have declined to the extreme. Although Anos entered the "Demon King Academy" where those who are identified as the reincarnation of the demon king are gathered, the academy cannot see his strength and he is branded as an unfit person. In an environment where everyone looks down on him, he takes Mishana, the only girl who treats him kindly, as his subordinate, and the unfit person (demon king) reaches the pinnacle of the demon class system!