During Japan's Edo period, a clan of warriors emerged possessing a highly specialized, magical ability. Known as the Manyuu, this clan mastered the technique of delivering sword strikes capable of reducing the size of a woman's breasts. While such a power might not appear sufficient to dominate a region, in the world of Manyuu Hikenchou, large breasts signify status, wealth, fame, and influence. Serious concern has gripped the Manyuu clan regarding the actions of their designated successor, Chifusa. Repulsed by the breast-obsessed society that the Manyuu have created and sustained, Chifusa has not only abandoned the clan but also stolen the sacred scroll detailing their methods for enlarging and severing breasts. Fortunately, Chifusa is not entirely alone. Her fellow warrior, Kaede, sympathizes with her cause, a stance that could place her in significant danger. Now hunted by the very clan that raised her, Chifusa must protect both her own life and Kaede's while attempting to reverse the harm their relatives have inflicted upon the land. Along the way, Chifusa will discover that she possesses a power far exceeding her training, one that could help reshape and transform the land she strives to make equal.