 Watsuki created him to be Kenshin's best friend, who is willing to punch him when he is sad to make him "wake up" from his sadness.Although Sanosuke is a main character in the series, Watsuki felt that he could not write everything he wanted about him, and thought that making him the title character of a series would prove interesting.The character is based on Shinsengumi member Harada Sanosuke.