Kamakura Hiren Houjou Koigayatsu

After the death of Yoritomo, the Hojo clan's regent, Tsunetoki, lost his backing and married off his 16-year-old sister, Princess Hikawa, to the 7-year-old shogun. But who did his sister really love? She fell into the valley of love. Set in Kamakura, this is the story of men fighting political enemies and the women who loved them.

(Source: Akita Shoten, translated)

Note: Includes one extra chapter.