Ooku: The Inner Chambers v1 - I'm not sure exactly how that title is supposed to be pronounced. I know what I like and I liked this story. The series looks like it will be a series of stories from different points in history.
What's it about? In the world this story takes place, at the beginning of the 17 century, most (75%) of the men of Japan have been killed by a plague that only affects men. Introduced halfway through the book, the Shogun, Yoshimune, is a woman. The first three of four chapters in this volume are about Mizuno, a young man who joins the Shogun's Ooku, which is essentially a harem. The last chapter seems to set a framing convention for telling more stories.
For more about this volume I recommend reading this review.