Shun Aoi, the older brother of Ashito Aoi, is a former footballer forced to abandon the sport after severe childhood asthma attacks culminated in a traumatic incident during Ehime FC Junior tryouts, witnessed by coach Jinbachi Ōshita. This event led to a prolonged avoidance of football, which he felt had "betrayed" him, though he retained a deep love for the game that later influenced his actions. Academically gifted enough for Keio University, Shun prioritized family responsibilities over personal ambitions due to their financially struggling background. He balanced part-time work, studies, and supporting his family after his father's absence, even using his own savings intended for his future to fund Ashito's tryout expenses for Tokyo Esperion. He saw Ashito as the outlet for his own unfulfilled football dreams, believing he lacked the necessary mental and physical strength himself. Shun exhibits practicality, loyalty, and a strong sense of duty, aligning with the ISTJ personality type. He is reserved and introspective, often suppressing his own desires to protect his family, such as hiding financial discussions about football from his mother, Noriko. His Enneagram Type 3w4 traits show a drive for achievement and validation, though he initially placed others' needs before his ambitions. A pivotal moment occurs when Shun reengages with football. Witnessing Ashito's admiration during an interview triggers guilt for "running away" from his past trauma. Encouragement from his friend Nanami Shiina, who challenges his avoidance, prompts him to play in an intramural match. There, he scores a decisive corner kick, symbolizing his reclaimed courage and attracting Ōshita's attention for a second professional chance. In the spin-off *Ao Ashi Brotherfoot*, Shun joins Athletica Club Ehime in the J2 League. He undergoes rigorous physical training to manage his asthma and rebuild confidence. His technical skills, particularly his left-footed kicks and spatial awareness ("Wide Vision"), are noted, though less pronounced than Ashito's "Eagle Eye." Shun's leadership evolves as he learns to rely on teammates and coaches like Ōshita and Makoto Kenzaki. He mends family communication by openly expressing his desire to play while self-funding his pursuits. Key relationships mark his growth: - With Ashito, he transitions from living vicariously through his brother to a relationship of mutual support and regular encouragement. - With Noriko, he moves from secrecy to honest conversations about his football aspirations, acknowledging her influence on his resilience. - Nanami Shiina's candid interventions help him confront his fears and prioritize his happiness. - Teammate Daigo Shiraishi's bluntness inadvertently solidifies Shun's self-belief during tryouts. Physically, Shun has average height, a lean build, black hair styled to the side, and wears black-rimmed glasses, switching to contact lenses for matches. His journey culminates in a balanced commitment to football, family, and academics, symbolizing his overcoming of past limitations and pursuit of his own dreams.