King Yasha is the King of the Yasha clan and a warrior god of the North. He is a crossover character from CLAMP's RG Veda. He also happens to be the strongest one out of the four warrior gods. His given name is Yama, that is what it was before he became Yasha.
After he heard the Prophecy from Kuyo, he became very interested in the whole rebellion deal, so he went and broke Ashura's seal and freed him. After the Yasha clan was demolished because Ashura was brought into the village, Yasha and Ashura set out on their journey to find the other members of the Six Stars. Yasha is a pretty stoic person who doesn't like to talk much, but is very determined to defeat Taishakuten. Yasha is also Ashura's best friend. His Japanese voice actor is Hayami Show and his English voice actor is Yasunori Masutani.