Kōta serves as a detective at the same agency as Takuya and Yumiko. He possesses navy blue hair and light brown eyes, typically dressed in a hooded suit, black pants, and shoes. His personality emphasizes unwavering loyalty, particularly toward Yumiko, consistently demonstrated through his operational decisions and actions.

During a critical escape sequence alongside Yumiko, Takuya, and Yuki, Kōta provides assistance. Yumiko creates a diversion by shooting a door lock to seal it shut, ordering the group to proceed while she stalls pursuers. Amid the escape, Kōta is stabbed in the back by a throwing knife. Initially declared deceased in Episode 2, his survival of the injury is later confirmed in Episode 3.