Summoned by an evil spirit to sacrifice a young girl to the deity of the local temple, villagers call on Hayate, a demon hunter. To their surprise, the latter is none other than a beautiful white dog, endowed with great powers. With his help, they soon discover that the creature causing their troubles is none other than the kakuen Mashira, a being half-man, half-ape, with a habit of kidnapping humans. The latter, little unsettled by his meeting with the dog, decides to adopt him… Thus begins the tumultuous relations, "like dog and monkey", of these two supernatural beings according to the seasons of legendary Japan!