Shusui Hyou is Shuurei's main lady-in-waiting during her time as an imperial concubine. Her beauty is said by Ryūki to be comparable only to Kochou, the famous courtesan in the Red Light District. She loves the smell of sandalwood and had kept a fan made of sandalwood as a prized possession, though the fan is later given to Shuuei. Shusui is deeply attached to Shouka, although he doesn't return her feelings, and is the only person who says that his tea is delicious. She is terrible at embroidery, which Ryuuki likes to tease her about; when she attempts to make a sunflower-like floral pattern, Shōka mistakes it for a lion. Shusui appears kind and caring to Shuurei and Ryuuki, although Ryuuren is suspicious of her swift agility in dealing with Kourin's clumsiness.
It is later revealed that Shusui comes from the Hyou clan and she is to succeed Ruka as the leader of the psychics. When Shouka took Shokun away from the clan, he also brought Shusui, whom he brought into his care and sent to the palace. While Sa-Taiho believes that she is an assassin loyal to him, Shusui is actually a double agent under the orders of Advisor Sho, known as the Black Wolf and leader of an order of assassins known as Wolves of the Wind which is loyal to the Emperor.
In the second season of the anime, Shusui starts to hear sounds in her head; afraid that she is falling back into the control of the Hyou clan, she attempts suicide. When she passes out in Shuuei's arms, she breaks his heart by calling out Shouka's name instead. He later uses Shouka's name to snap her out of a hypnotic trance. Afterward, she insists on remaining in Ran province to face the Hyou clan, leaving her position as head lady-in-waiting of the Imperial Harem. She is deemed officially missing (though the Emperor knows where she is) and her position has been filled by Jyuusan-hime. In the 16th novel, Shusui is trapped in the "prison of time" and was later rescued by Shuuei.
