Karin, a precocious teenager, is abandoned by her father in rural Japan. Living in a temple with her grandfather, she meets Anzu, a giant “ghost cat” and infamous wanderer who is tasked with caring for her. Wary of her new guardian, Karin sabotages Anzu’s random missions for the townspeople and befriends the eccentric spirits of the local forest. In an attempt to win, Karin Anzu accidentally makes a deal with the devil, and all of Hades is set free.