|Anime Debut||Episode 29|
Kawaji served in the Meiji Revolution. One day, Okubo Toshimichi saw his talents and so he made him Police Commissioner.
He's loyal to the Meiji government. He threatened Himura Kenshin that Takani Megumi could be charged for opium manufacture if he didn't go to Kyoto to battle Shishio Makoto, to which Megumi simply said that she'd rather be executed than be involved in a conspiracy to blackmail Kenshin, although Kenshin eventually agrees to go, in order to stop Shishio Makoto.
He stopped Kenshin and Saitō Hajime from killing each other when they were dueling. He tells Saito that he was supposed to test Kenshin's skills, however the two of them got so involved in the battle that they were blind and deaf to everyone and everything else, except the voices of those who witnessed and lived through the Bakumatsu.
He was a good friend to Okubo and admired him greatly. He was deeply upset when Okubo died and that the true killer would never be brought to the surface, since other Samurais took the credit for what the assassination.
Kawaji has a very strict and hard personality, always taking the strongest measures to prevent disasters from occurring (such as Shishio's plan to destroy Japan).