Eleven-year-old Karin is abandoned by her father. He leaves her with her grandfather, a monk who lives in a temple in rural Japan. To watch over his granddaughter, the grandfather asks Anzu, his cheerful and helpful if somewhat moody ghost cat, to look after the girl.

But when the energetic personalities of both clash, sparks fly... but it may only be the beginning of a friendship that will take them to the afterlife in search of Karin's deceased mother.