Shinji Koganei, a second-year Seirin High basketball team member, balances his role as a versatile “Jack of All Trades” with a 170 cm, 67 kg frame and a distinct cat-like mouth, wearing jersey number 6 as a small forward. Initially exploring baseball, soccer, and swimming in his youth, he shifted to tennis in junior high before embracing basketball after witnessing teammate Rinnosuke Mitobe’s play. Early struggles included comical rule misunderstandings—like dubbing traveling violations “cycling”—and wavering commitment during rigorous training. However, Seirin’s Interhigh preliminaries defeat galvanized his resolve to improve, cementing his dedication to the sport. Friendly and talkative yet prone to pessimism under pressure, Koganei oscillates between a boisterous demeanor and moments of intimidation against formidable opponents. His resilience surfaces in critical matches, exemplified during the Winter Cup finals against Rakuzan, where he tenaciously screened Reo Mibuchi despite the latter’s reputation as an Uncrowned King. A unique bond with Mitobe thrives on intuitive non-verbal communication, underscoring their on-court synergy. In the *Last Game* narrative, Koganei supports Seirin’s efforts during the Vorpal Swords-Jabberwock clash, with his sister Akane observing his evolution from a self-centered middle school athlete to a team-focused player valuing collective success over personal accolades. Though absent from the Vorpal Swords lineup, his involvement in preparations highlights his steadfast presence as a collaborative teammate. Koganei’s trajectory traces a multi-sport foundation, near-abandonment of basketball, and eventual embrace of its challenges, reflecting growth from an uncertain novice to a determined contributor within Seirin’s dynamic. His arc intertwines perseverance with adaptability, anchored by a gradual shift toward prioritizing teamwork amid competitive trials.