Atsumu Miya, a second-year Inarizaki High student and the team’s setter, stands among Japan’s elite high school volleyball players. Defined by unshakable confidence, relentless competitiveness, and a perfectionist streak, his bold demeanor mirrors his golden-yellow hair and trademark smirks. He holds himself and teammates to exacting standards, openly challenging spikers who mishandle his meticulously crafted tosses—a habit that sparked clashes during his middle school years. Renowned for adaptive, inventive play, Atsumu instinctively replicated the "freak quick" attack mid-match at a national tournament, proving his ability to innovate under pressure. He relentlessly pursues precision, contorting his body for flawless overhand passes even in awkward positions. His powerful serves, delivered with laser focus, draw sharp reactions when interrupted, underscoring his intensity. The dynamic with twin brother Osamu Miya anchors his identity. As the "volleyball celebrity twins," their on-court synergy—Atsumu setting, Osamu spiking—fuels both rivalry and growth. Atsumu’s drive to outpace his brother intertwines with mutual reliance, a bond teammate Aran Ojiro credits as his core strength. Post-graduation, Atsumu honors this connection by choosing jersey number 11 with the MSBY Black Jackals. In his professional career, Atsumu sharpens his adaptability while sustaining rivalries, notably with Tobio Kageyama. He dissects opponents’ flaws during training camps, pushing peers to address weaknesses like Kageyama’s overthinking. Though his bluntness occasionally sparks tension, his charisma and unwavering dedication earn respect. Atsumu’s personality merges fierce ambition with playful provocation. He revels in competition, vocalizing frustration when bested yet channeling it into relentless improvement. Taunting rivals like Hinata Shoyo or needling Kageyama highlights his love for mental games. Beneath the bravado lies a capacity to acknowledge others’ skill, offering sincere praise when earned. His evolution from a gifted but abrasive high school athlete to a collaborative yet driven professional reflects persistent experimentation, tactical flexibility, and an unbroken bond with Osamu. This trajectory cements his role as a complex, pivotal force within the volleyball narrative.