During Japan's Edo period, a unique group of warriors emerged known as the Manyuu. Their magical ability involved wielding a sword strike capable of reducing a woman's breast size. Although seemingly insignificant, having small breasts in Manyuu Hikenchou equated to a loss of status, wealth, fame, and influence. The Manyuu clan now faces a pressing issue following the betrayal of their designated heir, Chifusa. Embarrassed by the society created and encouraged by the clan, Chifusa abandoned her leadership role and absconded with the sacred scroll detailing the techniques for breast augmentation and reduction. Chifusa has found an ally in Kaede, a fellow warrior who shares her convictions, but their safety is in jeopardy as they are pursued by their former clan. Chifusa must defend herself and Kaede while striving to rectify the harm caused by the Manyuu's antiquated hierarchy. As she embarks on her mission, Chifusa discovers a power beyond her training that could transform and bring balance to the land.