The Commander of the Shinsengumi, an anti-terrorism special forces unit. He is the man who built the Shinsengumi into a cohesive organization and commands deep trust from his men. However, he is hopelessly in love with Shinpachi's sister, Otae, and frequently engages in stalking behavior. He often ends up naked before anyone realizes it, making him a dangerous individual in more ways than one.

The cool-headed Vice-Commander of the Shinsengumi. He established the Kyokuchu Hatto (Code of Conduct) and is feared by terrorists and subordinates alike as the "Demon Vice-Commander" once he draws his blade. He is a heavy smoker and a severe mayonnaise addict. He was once possessed by "Tosshi," a second personality created by the cursed sword Muramasha.

The Shinsengumi's best swordsman. Despite his refreshing appearance, he possesses a dark and scheming inner nature. He favors using a bazooka and is constantly aiming for the Vice-Commander's seat. He tries to slack off on his duties at every opportunity. His personality is that of a total sadist.

A Shinsengumi spy whose only redeeming quality is his plainness, often pushed around by his unreasonable superiors. While he is mostly seen enjoying badminton or kabaddi during work hours, his abilities as a secret agent are said to be excellent... supposedly. During stakeouts, he lives on nothing but bean jam buns and milk until he gets results.