Saitō Hajime is the former captain of the third unit of the Shinsengumi, a manslayer, and currently a special agent for the Meiji Government's Department of Internal Affairs. Having a long-standing rivalry with Kenshin since their days on opposite sides of the Bakumatsu,  Saitō nevertheless holds a begrudging respect for Kenshin and has come to his aid on assignment more than once, acting as a ruthless ally and the voice of cynical reason in Kenshin's major battles.

(Saito has a deep voice and is very calm and collected. He also has a intimidating tone to his voice as well)