Yakumo Fuuji undergoes a bizarre chain of events that leads him to become the undying servant of the last surviving member of the 3 Eyed immortal race. The immortal, named Pai, saves Yakumo's life by assimilating his soul, thus rendering him immortal too. Together, they embark on a quest to locate a way for Yakumo to regain his human form. Naturally, their journey is complicated by various obstacles - including Pai's split personality disorder, which sees her oscillating between a disarmingly adorable persona and an aggressively destructive one - as well as romantic tensions that arise between them.
