Ashiya Michitomo, the legendary onmyoji hailed as the mightiest in the Heian era, is betrayed by his close friend and rival, Abe Seimei, resulting in the tragic massacre of his entire clan. Using a reincarnation spell, Michitomo is reborn in the modern world—a place where yokai (supernatural creatures) run rampant, and exorcists are revered as heroes for purging them. However, the Ashiya clan, once respected, had fallen into disgrace and contempt for betraying the Abe clan and suffering a devastating defeat. While the Abe clan has risen to power in the modern era, the Ashiya clan remains in ruin. Upon learning of his clan’s oppression due to his own defeat, Michitomo vows to revive the Ashiya clan and seek revenge against the Abe clan. He has devoted himself to rigorous training since childhood, aiming to awaken as the strongest onmyoji of the modern age. With the mightiest yokai by his side, who pledge unwavering loyalty, Michitomo embarks on a path of unrivaled dominance in the world of exorcists.