In a world in which having large breasts means everything, the successor of the powerful Manyu family, Chifusa Manyu, defects and steals the Manyu Scroll of Secrets (which contains all the Manyu secret techniques for breast enlargement), but is wounded during her escape. She is found by a woman who was recently attacked by Kagefusa, a Manyu assassin and Chifusa's sister, resulting in her breasts becoming small and effectively making her poor. The woman becomes jealous of Chifusa and attempts to sever her breasts in a fit of rage, but Chifusa manages to calm her down. As Chifusa is about to leave, she is confronted by Kagefusa, who had also captured Chifusa's comrade, Kaede, and severed her breasts. As Chifusa stands against Kagefusa, she uses a special technique which steals Kagefusa's breasts and adds them to her own. As Kagefusa is forced to retreat, Kaede decides to join Chifusa on her journey.