Friendship shared between Karin, a strong-minded girl sent to live with her monk granddad in the Japanese countryside, and Anzu, the even-more unpredictable phantom feline who acts as her guardian.

Karin, 11 years old, is abandoned by her father at her grandfather's house, the monk of a small town in the Japanese countryside. Her grandfather asks Anzu, his jovial and helpful although rather capricious ghost cat, to look after her. The meeting of their strong characters causes sparks, at least at the beginning.