TV-Series
Description
Koutarou Kobayashi is a twelve-year-old middle school student and classmate of the series' protagonist Misaki Suzuhara. He lives with his family, which runs a karate dojo, and he has a younger sister named Hatoko Kobayashi, who is a skilled Angelic Layer player despite her young age. His background in a martial arts household has given him some practical karate knowledge, which he occasionally draws upon when observing or supporting others in the game.

In terms of personality, Koutarou is generally shy and reserved, yet he possesses a quiet enthusiasm for the world of Angelic Layer. He is often seen as a gentle and supportive presence, though he can become flustered or embarrassed, particularly around Misaki, for whom he harbors a crush. A recurring source of frustration for him is the way his friend Tamayo Kizaki treats him: she has used him as a practice target for her martial arts since they were four, and she persistently calls him by the diminutive "-chan" suffix rather than the more masculine "-kun" he would prefer.

His primary motivation stems from his feelings for Misaki and his desire to see her succeed. He acts as a perceptive ally, often identifying her strengths and weaknesses during Angelic Layer matches and offering encouragement or tactical suggestions. This supportive role defines much of his presence in the story, as he cheers her on from the sidelines and tries to contribute even without being a Deus himself. When another boy, Ohjiro, begins to show interest in Misaki, Koutarou becomes visibly jealous and even impulsively attempts to engage Ohjiro in an impromptu Angelic Layer contest, despite having no personal experience playing the game himself.

Key relationships include his bond with his sister Hatoko, whom he cares for like a typical older sibling, and his complicated friendship with Tamayo, which mixes irritation with long-standing familiarity. His connection to Misaki is the emotional core of his character arc, driving him to step out of his comfort zone and take risks he normally would avoid.

Over the course of the series, Koutarou undergoes modest development. He grows from a passive onlooker into someone willing to take more active steps to support Misaki, even if his attempts are sometimes clumsy or driven by jealousy. His willingness to share his karate insight to help Misaki’s angel Hikaru demonstrates a growing maturity and a desire to contribute meaningfully. While he never becomes a central competitor, his role as a loyal friend and budding romantic interest gradually solidifies.

In terms of notable abilities, Koutarou’s strength lies not in Angelic Layer gameplay itself but in his analytical eye and his foundational karate training from the family dojo. He can spot tactical openings and patterns in battles and occasionally suggests practical martial arts moves that Misaki might translate into her angel’s actions. His real value is as an observer and a supportive teammate, making him a quiet but steady fixture in the protagonist’s journey.