Dairen Ou is one of the three thugs who attempts to fight Kenichi Shirahama after the latter's first battle with Boris Ivanov. He is a practioner of Hakkakuken and wears a skin-tight black shirt with lighter-colored outlines. Along with Jun Sanada and Tadamoto Kashima, Dairen desires to test his skills against Kenichi and easily blocks his normal attacks. However, he is just as easily defeated by Kenichi's Mubyoshi.