A giant demon bear named Akakabuto has seized control of Futago Pass. Shortly thereafter, a silver, tiger-striped Akita puppy named Gin is born and trained as a bear-dog. Gin is brought to Riki, the leader of a large dog pack and Gin's father, to join the group. Riki allows him to join after Gin proves his strength, and he dispatches his platoons to various parts of Japan to recruit strong males to fight Akakabuto. Gin, a third-generation bear-dog, endures many hardships with the aim of stopping the terrifying bear, Akakabuto.