Sayuri Kokusho (born December 22, 1966, Kagoshima) was the unofficially acknowledged leader of Onyanko Club. She sang lead on numerous Onyanko Club songs and sometimes had them singing back-up for her solo songs. When the Onyanko Club guest starred on Sukeban Deka II on the episode "Onyanko Club o Zennin Zuchu", Sayuri had a featured role. The highlight of the show was when she led the Onyanko Club on her song "Valentine Kiss", her best and most popular song. Sayuri once challenged herself by riding her motorcycle across the United States.