Koutarou Miyao is a supporting character in Hi Score Girl II who has been a close friend of protagonist Haruo Yaguchi since middle school. Their friendship continues into high school, where Miyao remains a steady and reliable presence in Haruo’s life. He is intelligent, academically capable, and widely regarded as handsome, which makes him popular among his female classmates. Miyao presents a bright and composed demeanor, and he approaches social situations with sensitivity and thoughtfulness.

Personality-wise, Miyao is defined by an earnest kindness and a genuine desire to support the people around him. He is not judgmental and tends to give advice from a place of care rather than criticism. His empathy allows him to read subtle emotional undercurrents, and he often understands the romantic tensions among his friends better than they do themselves. Despite his own appeal and the confessions he receives, he does not enter casual relationships and instead prioritizes the feelings of others. His gentle nature sometimes leads him to put his own emotions aside for the sake of his friends’ happiness.

Miyao’s motivations are rooted in loyalty and a protective instinct toward Haruo. He considers himself Haruo’s best friend and acts almost like an older brother, offering guidance on matters that Haruo finds perplexing, especially romance. He wants to see Haruo grow and succeed, not only in the arcade but also in life. This supportive drive extends beyond words: when Haruo decides to aim for a difficult high school entrance exam, Miyao helps him study without hesitation. He also remains present at critical moments, such as observing the high-stakes gaming match between Haruo and Koharu Hidaka, where he quietly processes the emotional stakes involved.

His role in the story is that of a perceptive observer and occasional mediator. He frequently serves as a sounding board for Haruo’s confusion and provides insight that the more game-obsessed Haruo tends to miss. Miyao is not a competitive gamer himself, but he respects the arcade culture that binds his friends. He often finds himself aware of multiple layers of unspoken feeling: Haruo’s deep connection to Akira Ono, Koharu’s affection for Haruo, and the complicated triangle that emerges. When he recognizes that his own brief romantic interest in Akira would only complicate matters, he quietly withdraws, further demonstrating his selflessness.

Key relationships center on Haruo, to whom Miyao is fiercely loyal. He refers to himself as Haruo’s best buddy and never wavers in that commitment. Toward Akira Ono he harbors no resentment; instead, he acknowledges the unique bond between her and Haruo and supports it from a distance. He also understands Koharu Hidaka’s position and, while he does not manipulate situations, he sometimes gently nudges Haruo to consider her feelings. His friendship circle is small but tight, and he values harmony within it.

Over the course of Hi Score Girl II, Miyao’s development is subtle but consistent. He continues to mature in his ability to offer emotional support without intruding, and his decision to step away from his own crush in middle school solidifies into a lasting principled stance. He learns to navigate the evolving dynamics of high school while remaining a stable anchor for Haruo. His notable abilities lie in his social intelligence: he is perceptive, articulate when giving advice, and emotionally resilient. These qualities make him an indispensable friend who often serves as the emotional compass of the group, quietly ensuring that no one disappears into their own isolation.