Sato is a childhood friend of Mr Miyagi. They were both taught Karate by Mr Miyagi's father. When young, Sato, insulted by the announcement of Miyagi wanting to marry his betrothed, challenges Miyagi to a fight. Mr Miyagi instead leaves the village (Okinawa), choosing not to fight his best friend. When Mr Miyagi returns to Okinawa before the death of his father, Sato challenges Mr Miyagi once again. When refused, Sato names Miyagi a coward.A typhoon destoys Okinawa, in which Sato is injured. Miyagi rescues him, which appeases Sato's anger and Miyagi & Sato are once again friends. Sato's nephew and best student Chozen displays cowardice during the typhoon, which leads to Sato disowning Chozen.