Jouyuu (冗祐) is a hinman and is one of Keiki's shirei. At the beginning of the series, Keiki orders Jouyuu to 'attach' to Youko to enable her to fight. He is told to go dormant when Youko gets upset that she can feel him squirming in her. When Keiki is captured by Kourin, Jouyuu is his only shirei to remain free and unbound because he had been attached to Youko, who had not been captured along with Keiki.
Though Jouyuu ensures that Youko is able to fight and protect herself, he loyally adheres to Keiki's command to be otherwise silent and unnoticeable in Youko's presence. He disobeys the order only twice - once when he notices Keiki has been captured in Kou and second when Youko doubts that she possesses the qualities required to become the new ruler of Kei. Jouyuu expresses that he has seen Youko changed to become a person aware of herself from someone who would whine and become upset easily, believing that she is capable of becoming a king.
After Keiki is freed, Youko requests that Keiki revoke the order that Jouyuu remain silent so she may communicate with the hinman and thanks Keiki for leaving Jouyuu to protect her.