yWho is the "Devil"z __ 20 ~ Year, Kanagawa Prefecture ? Heijin-shi. At midnight, the clock is clocking the new date. Four people were gathered to surround the flame of a candle lit in the darkness of jet black. School girls, a good man, long-haired youth, young boys remaining. Make sure that the four people with ages and sexes gathered together, One of them opens his mouth. "- Did you find the next Demon Lord?" Along with that word, their appearance changes completely. Rashless black feathers, sharp corners, violent engravings in the crimson eyes - a figure of irregular shapes that can not be called human beings. Yes, they are not human beings. In order to find the successor of the demon king who lost his life in the fight against the enemy called "Teruishi" It was the four heavenly king of the Makai that came from the other world with the guidance of the book of Seika selection. Although it is a famous existence in Makai, there is no knowledge of this human world at all. Although we are hiding under the circumstances and gathering information, we have no results as expected. A hero who is one of the four heavenly kings - Aika also felt impatient about the situation without progress. One day. Each of the four heavenly kings keeps track of "a man with demonic qualities". However, out of the four "demon king candidates", it can not be determined at this moment who is the real demon king. So the hero and the four heavenly kings follow the guide of the selection, They will explore their qualities as demon kings.