During the rule of Tokugawa Iemitsu, the third Shogun of the Tokugawa shogunate, a boy was attacked by a bear in a rural village in the Kantō region, which triggered the spread of a strange disease later known as the "redface pox." No cure or treatment was ever discovered for the disease, except that it "only affects young boys" and has an "80% fatality rate." As a result, the male population plummeted to about one-quarter of the female population, and the social structure of Japan was drastically changed. Boys were raised as scarce stallions and were forced to either go to grooms, be rented out to poor families who could not get grooms at any price per night, or sell their bodies in the brothels. On the other hand, women replaced men as the main labor force, and all family businesses were handed down from woman to woman. In Edo Castle, too, the shogunship was handed over to women after the third Shogun, Iemitsu, and the Ōoku attracted endangered young men as proof of the Shogun's prestige, creating a world of men commonly referred to as "three thousand beautiful men."