Kiho Kurihara is an 18-year-old high school student who integrates into a close-knit friend group during high school, joining Kadode Koyama, Ouran Nakagawa, Ai Demoto, and Rin Hirami. While the other four shared pre-existing bonds, Kiho arrived later, a dynamic fueling occasional feelings of exclusion and insecurity about her place within the circle. Her personality includes a quick temper, frequently sparking arguments, particularly with Ouran. She maintains a stylish appearance and prioritizes her looks more than some friends, alongside an expressed interest in concepts like "girl power."

She begins dating Kenichi Kohiruimaki, a previously isolated classmate. This romantic relationship creates distance from her core friends as she spends less time with them. After she and Kenichi break up, she reconnects with the group, restoring their previous dynamic.

Kiho's story ends tragically during an incident related to the alien presence over Tokyo. She is killed when a military strike downs an invader spacecraft; the vessel crashes either at Kichijoji station or near her apartment during the New Year's holiday. Her death occurs abruptly and off-screen, noted as one of three casualties. It is presented as a sudden, realistic tragedy without extensive dramatization. In the aftermath, her friends grieve but continue their daily routines like attending school, with classmates moving on quickly. An emotional outburst from Ouran helps the group collectively process their grief before gradually resuming normal life.

Her former boyfriend, Kenichi Kohiruimaki, becomes radicalized following her death, forming a vigilante group dedicated to retaliating against the alien invaders.