Hikari, who was to work as the youngest maid in Ooku and was given the name of Ukifune, took on the difficult work as "yes, please" and gradually made use of the wisdom she learned as a child. It will become a presence that will be seen from the surroundings. The best Cinderella story in Japan that depicts the life of Keishoin, who was the concubine of the third shogun Tokugawa Iemitsu and the birth mother of the fifth shogun Tsunayoshi Tokugawa, who climbed to the top of Ooku from the common people!