Uikyou

Uikyou is an anime-only character and serves as the Taishi of Kei for Youko until she is displaced.

She is depicted as a friendly woman who sincerely appreciates all of Youko's efforts to become an effective ruler, answering all Youko's questions as well as informing Youko on why she cannot act on certain decisions.

With Koukan and the Taisai (the Palace Administrator, the Mandarin of the Ministry of Heaven), Uikyou and the other Sankou had conspired together to remove Youko from the influence of Seikyou, the corrupt chousai, the Prime Minister of the court. When Uikyou attempts to spirit Youko away during a private dinner, Seikyou and the Minister of Law's men appear with a false charge that Uikyou is part of a scheme to assassinate Youko. In desperation, Uikyou tries to take Youko hostage, but is shot to death with arrows. No longer certain who to trust in court, Youko winds up exiling Koukan and the remaining members of the Sankou after the Taisai is mysteriously killed and demoting Seikyo and the members of his faction.

In the credits of the anime she is referred to her rank, Taishi (太師).

(Source: wikia)