The captain of the 1st Division of the Shinsengumi, the Edo period police force, he holds the title of the strongest man in the Shinsengumi. Despite his fresh appearance, he possesses a significantly twisted and warped personality. He constantly delivers venomous remarks with a deadpan expression. A troublemaker who acts delinquent and selfish despite being a police officer, he often causes chaos whenever he is deployed. He is stubborn, highly competitive, and hates to lose, often staking his life on contests like a child, and he genuinely enjoys fighting. He never reveals his weaknesses to others. While he appears arrogant, indifferent, and relaxed due to his constant poker face, he has a delicate side, even referring to himself as a 'glass sword.' He is a massive sadist who finds the joy of life in tormenting others. If told not to do something, he wants to do it even more. However, he suddenly becomes a fool when he finds himself on the receiving end. Though he seems haughty on the surface, he often shows intense self-deprecation in serious moments. He is a loyal and affectionate person at heart. He is extremely devoted to those he likes and will risk his life for those he cherishes. In particular, he is completely loyal to Kondo, the Commander of the Shinsengumi, and turns into a gentle lamb in front of people he truly likes. Surprisingly, he has a strong sense of justice and a thorough sense of duty as a police officer. Outside of work or slacking off, he spends most of his time tormenting the Vice-Commander Hijikata or plotting schemes to harass him. He never smokes. He has a subtly kind and delicate side, making him a 'dere' who never shows it. Basic manners are ingrained in him. He usually avoids physical contact, but if he loses his cool, he becomes a bulldozer. When drunk, he has a habit of hugging the bottle and laughing (he drinks despite being a minor). His swordsmanship is considered the best within the Shinsengumi, and he is incredibly powerful.