Kōrai Hoshiumi serves as a second-year wing spiker for Kamomedai High School's volleyball team. His relatively short stature is counterbalanced by exceptional athleticism, particularly a remarkable vertical jump enabling effective spikes against taller blockers. He possesses distinctive snow-spiked white hair and noticeable dark circles under his eyes. His high school hairstyle was upward and voluminous, later becoming shorter and neater as an adult. Hoshiumi exhibits a personality blending confidence with sensitivity. He remains composed during matches but displays vocal enthusiasm off the court. Actively seeking recognition, he often expresses frustration when opponents underestimate him due to his height or when his skills fail to surprise them. This stems from an early awareness of his physical limitations, recognized by third grade in middle school. Initial distress over his height transformed into determination through his mother's encouragement, driving him to refine technical skills and become a top-tier player regardless of constraints. His volleyball journey solidified at Kamomedai High as the team's ace and primary offensive weapon. His national-level performances drew attention, including direct comparisons to Hinata Shoyo. Kageyama Tobio noted Hoshiumi's jumping prowess exceeded Hinata's during their high school encounters. His style combined power, precision, and adaptability, making him a versatile outside hitter crucial for both offense and defense. Transitioning professionally, Hoshiumi joined Japan's V.League team, the Schweiden Adlers. There, he became teammates with Kageyama Tobio, whom he met earlier at a national youth training camp. This alignment placed him among top competitors. He later joined the Japan National Team, showcasing elite skills internationally. Key details include his preferred food (shrimp flavored with plum), his ongoing concern about diminishing underestimation from opponents, and his physical growth: he grew only 4 centimeters between 2013 and 2018, significantly less than Hinata's near 9-centimeter increase in the same period.