Kamiyama was a member of the Muhou School and one of the men the serve Riichirou. It was confirmed by the author that he's a Corps Commander of unknown rank.
Kamiyama is an average man with long black hair that is tied back with a ribbon and two bangs hanging from the side. He wears a white overshirt with black shoulders, pads, and the Muhou School Symbal on the sleeves and back, over a black undershirt, white pants, black socks, and sandals.
Kamiyama is a calm person. He is also very loyal to Riichirou as he is willing to jump infront of an arrow aimed at Riichirou.
At point Kamiyama had joined the Muhou School and became one of the men the serve Riichirou. He was appointed Corps Commander.
Kamiyama accompanies Riichirou and the rest of his men, to the Anayaka Forest. Once they arrive at the battle, Kamiyama surrounds Zenmaru along with some other men. He then tries to attack Zenmaru along with the others, but they are blocked by Iori and Kizaki. He then battles them until Arata and his archers arrie to support the Ogame School. When Arata launches an arrow at Riichirou, he steps infront of it and loses his arm. He then notes how powerful it is and then fall down and dies.
It is unknown what Kamiyama was capable of as he was killed before he could show what he was capable of. Given that he was one of the Corps Commanders serving under Riichiro himself, he supposedly was quite skilled.