Kamiyama is a member of Shinsengumi 1st Division which is under the command of Captain Okita Sougo. He is one of the five Shinsengumi members (also led by Okita) that raids the Rokkaku Inn to thwart a bombing plan by the Joui extremists hiding there. He ends up slaying Rokkaku Muneharu, the owner of the inn, when the latter attacks him. However, after learning that Rokkaku has been threatened into cooperation with the extremists, he and Okita lie that Rokkaku is an innocent civilian killed by extremists in the crossfire. He and Okita are the only members of the Shinsengumi team to survive the Rokkaku Incident.
Wear a pair of spectacles with curly swirls, short black hair with side parting, on top of his regular Shinsengumi uniform.
Kamiyama has an obsessive infatuation with Okita and makes sexual advances to his superior by pulling down his pants or suggestively asking to be "stabbed." He is so persistent that Okita retaliates by stabbing him with Kirie's weapon.
He is also genuinely concerned for Okita's well-being and eventually reveals that his Captain is targeted by Joui extremists even though Okita has forbidden him from doing so.
Despite Kamiyama's overbearing sycophancy in Okita's presence, he saves Okita's contact as Ultra-S(adistic) Idiot (ドSバカ, do S baka).
- Okita Sougo: He is Kamiyama's superior and fellow survivor of the Rokkaku Incident. Kamiyama has an unrequited infatuation on him.
Kamiyama is the only member of the Shinsengumi team apart from Okita to survive the Rokkaku Incident. During the mission he approaches Rokkaku Muneharu and tries to offer assurance but is attacked by the inn owner. He kills Rokkaku in self-defense and later violates bureau policy with Okita by lying about Rokkaku's involvement with the Joui Sokai Faction to protect the dead man's honour.
He spots Okita flipping through old Shinsengumi records of the Rokkaku Incident and admits that it is during the Incident that Okita "captures his heart." He becomes indignant upon learning of Kirie's (ultimately proven untrue) accusations and attempt on Okita's life and wants to tell her of the truth but is stopped by Okita. Okita observes that Kirie's weapon is "a good blade that is well-used" and not something an ordinary citizen will have and hence deduces that there may be other survivors of the Rokkaku Incident who are using her. He then orders Kamiyama to find out more. Gintoki later stops Kamiyama to find out what Okita is concealing about the Rokkaku Incident.
Together with Shinsengumi and Yorozuya, he comes to assist Okita who is corned by a revived Sokai Faction. However, their lie is exposed in the process and consequentially, both are punished with exhausting paperwork for giving false statements. As he is punished, he expresses hope that Kirie will be able to lead a happy life.
Kamiyama is among the survivors of the battle. He follows his colleagues and heads towards the universe.
- Kamiyama has the same Japanese voice actor as Mousse from Ranma ½ and Iruka Umino from Naruto.