The main character and 62nd successor to Hokuto Shinken. Known in Shanghai as "Yán Wáng" (閻王, En'ou). Loves smoking cigarettes, reading, and has a good smelling instinct. His fighting technique is similar to Toki, in which he fights in a fluid and smooth fighting style. In Japan, he's a lecturer at the Touwa Women's University.

Depicted as somewhat easy going, as well as comical; compared to his namesake and nephew, Tetsuo Hara describes Kenshirou Kasumi as a combination of the strength of Kenshirou, the good nature of Keiji Maeda from Hana no Keiji and the sarcastic attitude of the title character of Nakabou Rintarou. However, remains the stoic persona which would be eventually seen in his nephew. He uses the same catch-phrase as his nephew, "You're already dead" (お前はもう死んでいる, Omae wa mou shindeiru), but pronounces it in Chinese, "Nǐ yǐ jīng sǐ le" (儞已經死了). Despite the fact that his father Tesshin is the successor of Hokuto Shinken, Kenshirou is revealed to be descended from the Hokuto Souke bloodline from his mother's side of the family.