Tetta Kisaki is the secret leader of Valhalla and one of the main antagonists in Tokyo Revengers. Known for his cunning intellect and ruthless ambition, Kisaki manipulates events from the shadows to achieve his goals. He uses Valhalla as a tool to challenge and destabilize the Tokyo Manji Gang (Toman), exploiting its members to serve his plans. Despite lacking physical strength, Kisaki's strategic mind and ability to control others make him an exceptionally dangerous adversary, driving much of the conflict in the series.