There is an isolated island "Himeno-jima", far from the main land. There is a provincial custom taken over for generations, which is "Nyuki Taisai". The girls who have the most beautiful bodies in the island are offered as oblations every year for rich harvest, and the men ejaculate on them. Same as every year, two girls are picked up, and Haruhiko is asked to train them to make them as indecent as possible by "Nyuki Taisai".