Description:

Ooku - In the beginning of the 18th Century a mysterious epidemic strikes the country of Japan, dropping the population of men to one fourth of its prior state. With this drastic reduction of men, more and more families struggle just to maintain their lives. Gender roles have been reversed, with women taking traditional male roles and men becoming little more than reproduction tools.

While more and more males are sought out for their ability to produce children, a 19 year old young man named Mizuno hopes to marry his childhood sweetheart, but due to their class differences he realizes this is almost impossible. To raise his social status and also save his poor family, Mizuno, who pursues the Samurai spirit even in this parallel world, enters the Ohoku (inner chambers of the Shogun's castle) and attempts to vie among 3,000 other men for the affection of the female Shogun.