Волшебное лето

Kouichi Uehara, a fourth-grade student living in the suburbs of Tokyo, discovers a stone that turns out to be a petrified kappa who has been sleeping underground for the past three hundred years. Kouichi names the kappa Coo, and they become good friends. Coo decides to live with Kouichi, but struggles to adapt to modern life in Tokyo and begins to miss his own kind. The new friends then embark on an adventure-filled journey to find Coo's companions.