Kirishima is a minor supporting character in Yu Yu Hakusho, best known as a close friend and loyal follower of Kazuma Kuwabara. He is one of the members of Kuwabara's gang of students from Sarayashiki Junior High, consistently appearing alongside his friends Okubo, Kato, and others. In terms of background, Kirishima is depicted as a normal human teenager with no spiritual or supernatural abilities, placing him firmly within the everyday world that the series' spirit detectives work to protect.

Regarding personality, Kirishima is characterized by his unwavering loyalty and deep respect for Kuwabara, whom the gang views as their leader. Among his friends, he is portrayed as the most intelligent and perceptive, though this is a relative distinction within a group that struggles academically. On one occasion, he correctly deduced that Kuwabara was feeling down because he had been rejected by a girl, demonstrating a level of emotional insight that his companions lack. His intellectual edge is further highlighted by a test score of 52 on a chemistry exam, which was notably higher than the significantly lower scores received by the other gang members. Kirishima's primary motivation is simple and consistent with his role: he wants to support Kuwabara, maintain the solidarity of their friend group, and navigate the challenges of junior high school life.

Kirishima's role in the story is that of a supporting civilian character. His presence serves to ground Kuwabara in the human world, highlighting Kuwabara's life as a tough but honorable student before and after his involvement in supernatural conflicts. In several early episodes, Kirishima and the gang are victims of incidents that require intervention from either Yusuke Urameshi or Kuwabara. For instance, he was knocked unconscious while trying to help protect Keiko Yukimura from rival gangsters. He was also seriously injured by a group of half-breed demons who were impersonating students from a rival school, an act that provoked Kuwabara and Yusuke to seek revenge. Later in the series, he and his friends were attacked by the psychically gifted student Mitarai, an event that was subsequently erased from their memories, returning them to their normal lives unaware of the danger they had faced.

Key relationships define Kirishima's entire presence in the series. His most significant relationship is with Kazuma Kuwabara, whom he admires and follows faithfully. He is also close friends with the other members of Kuwabara's gang, including Okubo and Kato, functioning as an integral part of that tight-knit group. While his interactions with main characters like Yusuke and Keiko are limited, they are always cordial and occur within the context of the gang's collective activities.

Kirishima does not undergo significant character development over the course of the series. His role remains static; he is a loyal friend and a regular student who occasionally finds himself in the crossfire of supernatural battles, only to have his memories wiped or to be saved by more powerful allies. His appearance, however, differs notably between the original manga and the anime adaptation. In the manga, Kirishima is drawn as a bishonen, or a notably handsome young man, with fair hair that makes him stand out from his companions. In the anime, he is given a more generic and unremarkable design, with brown hair and brown eyes, making him blend in more easily with the other members of Kuwabara's gang.

Regarding notable abilities, Kirishima has no special powers, combat training, or spiritual awareness. His only distinguishing traits are his relative intelligence compared to his friends and his steadfast loyalty. He is a normal human whose primary function in the narrative is to represent Kuwabara's ordinary life and to be a person in need of protection from the demonic and psychic threats that the main characters confront.