Ryuchi Kai is the General's son and another war veteran, who is a Yakuza boss and every bit as deadly and brilliant as his father but has earned a reputation for swift brutality. Astonishingly, despite the high level of discretion surrounding Noh, Kai manages to infiltrate the agency, personally, by using its policy of masked operatives to his advantage. He poses as Oni – one of the General's two overseers of the assassins (the other being a mysterious old man named "Dove"). He manipulates Kabuki and her partners into eliminating the entire underworld hierarchy in Tokyo. Publicly Kai is a talented businessman with much stock and influence in the Japanese market, thus this move makes him indispensable and essential to the balance.