Hajime Tamiya, nicknamed "Shokichou" (Secretary), runs with the Musashino Saru gang. This nickname reflects his meticulous, observant habit of constantly writing things down. As a teenager immersed in urban street culture, Tamiya actively engages in the gang's escalating conflicts, especially after fellow members are killed. He joins Kai and Hasheem investigating the deaths in Bukuro, placing him directly in the violent confrontations between the Musashino Saru and the Wu-Ronz. His role primarily involves supporting key gang members during these investigations and clashes. Tamiya wears glasses.