Karin, a precocious teenage girl, finds herself abandoned by her father in rural Japan. Living in a temple with her grandfather, she meets Anzu, a giant “ghost cat” and infamous bum who is tasked with watching over her. Distrustful of her new guardian, Karin sabotages Anzu’s random searches among the townspeople and befriends the eccentric local forest spirits. In an attempt to defeat Karin, Anzu accidentally makes a deal with the devil, and all of Hades breaks free.