Shishou (砥尚, Shishō) was the king of Sai who succeeded Fu-Ou, the Levy-King. Posthumously, Shishou is known as Go-ou (梧王). His aunt and adopted mother, Kouko, eventually succeeded him as the ruler of Sai.
During the reign of Fu-ou, Shishou had become outraged at the corruption of the kingdom's officials and led a revolt that gained sufficient momentum that the Levy-King's reign ended. The group led by Shishou was held in high-esteem by many for its good intentions and Shishou himself was known to be well-educated and idealistic.
To become the king of Sai, Shishou had ascended Mount Hou after the death of the Levy-King. The eight-year-old Sairin recognized that he possessed Ouki and chose him to be the next king of Sai. At the beginning of his reign, he presented Sairin with the treasure of the kingdom of Sai, the Kasho Kada, a jewelled branch that showed visions of prosperity, as a promise to make their kingdom as prosperous as her dreams would be. After becoming king, members of his faction, including his cousin Eishuku and Eishuku's wife, Shuka, obtained high ranking positions in court. His father Daishou, his aunt Shinshi, and his younger brother Junkou were given the ranks of the Sankou.
However, Shishou's reign lasted only twenty years, as his actions while he ruled caused Sairin to contract shitsudou. Unable to see why his reign was unable to bring about prosperity, he stubbornly clung to the idea that he and his court were being given trials from heaven to overcome. When it became apparent that Shishou would not be able to see that his ideal kingdom could not be applied to reality, Eishuku pushed him toward ruin by manipulating Shishou into using the Kasho Kada, which cemented Shishou's belief that the kingdom was on its way to becoming prosperous despite evident signs that it was not. As the court began to fall apart, Shishou realized that he had lost his way and ascended Mt. Hou to abdicate his throne. His last words were that "nothing could be gained by blaming others", as a reflection on his own ability and inability to rule.
In spite of his ineffective reign, Shishou was mourned by many upon his death. However, by renouncing his throne and taking his life, Sairin's life was spared and she recovered from shitsudou, allowing her to choose Shishou's aunt Shinshi as his successor.