One day, Yoshimi Satomi, the castle owner of Takita Castle in the country of Anbo, and his confidant Daisuke Kinba, on the way to hunt wild boars, felt sorry for a small dog that was about to be swallowed by a giant snake like a giant tree, and killed the serpent in a fierce battle and saved the puppy. Yoshimi decided to keep the puppy, naming it Hachibo. Now the Serpent Demon is determined to destroy Takita Castle, while Hachibo defends it with his life. His spirit is split into eight, and eight brave warriors must unite to defeat the demoness snake.