The reincarnation of the strongest beings from another world... an ordinary life is already out of the question. The Heavenly Demon, who had the unification of the world within his grasp. After perishing together in a final showdown with his sworn enemy, the Ice Witch, the pair is reincarnated as ordinary twin siblings in the human world. However, the peace is fleeting. Now teenagers, they find the world being shaken by organizations of reincarnators. The world simply won't leave these siblings alone as they try to live while hiding the powers of their past lives. Old subordinates gather one by one. And the Ice Witch now stands by his side—not as an enemy, but as a partner. Will the Heavenly Demon be able to become the world's strongest once again?!