Koharu is a student at a vocational school, where she meets Kiui Watase. She first encounters Kiui and Kano Yamanouchi during a motorcycle license training course. She is recognized for her striking, nonconformist appearance, often characterized by dyed hair, and she openly acknowledges having undergone multiple cosmetic procedures. Despite what some might perceive as a delinquent exterior, Koharu possesses a kind-hearted and deeply observant nature. She is remarkably non-judgmental and seeks genuine, tangible human connection. Her primary role within the story is as a grounding force for Kiui Watase. While Kiui thrives as their confident VTuber persona, they struggle immensely with social anxiety and face-to-face interaction. Koharu acts as a bridge between Kiui's isolated physical reality and their successful digital life. Unlike other peers who might be intimidated by Kiui's absenteeism or social quirks, Koharu approaches them without prejudice. She persistently offers kindness and friendship without any expectation of reciprocation or benefit. This creates a safe space for Kiui to exist as themselves, away from the demands of their online persona. Their relationship is built on mutual respect as social outliers who have found common ground. Koharu's persistent friendship is instrumental in Kiui's gradual character development. She helps Kiui navigate the pressures of maintaining a dual life and facilitates their gradual reintegration into real-world social spaces. Through their interactions, the story explores the theme that digital fame cannot substitute for tangible, face-to-face friendship. Koharu's most notable abilities are emotional and social. She possesses a high degree of empathy, patience, and social intuition, allowing her to see past Kiui's defenses. She is the character who most directly validates Kiui's real-world existence, contrasting with the attention Kiui receives from their online fans.