Kozue Nekoda operates as a substitute player for the Aota Academy girls' volleyball team. She displays orange hair arranged in pigtails, red eyes, and stands 1.71 meters tall. Her team jersey remains perpetually unzipped and knotted beneath her chest, highlighting her physical form.

As a bench player, Kozue voices strong frustration over her restricted playtime, a consequence of erratic match performance. Her gameplay shows marked inconsistency, frequently undermined by concentration lapses. Despite these challenges, she projects an extroverted, attention-craving persona. She overtly directs flirtatious advances toward the team's coach, Motoura, leveraging her appearance to capture his focus.

A critical incident unfolds when Kozue confronts a sexual assault attempt by three attackers in a park. Coach Motoura intervenes to rescue her but vanishes immediately after the confrontation. This event sparks a comprehensive team search and introduces instability within the volleyball squad as they ready for championship games without their coach.

Kozue's portrayal remains uniform across media, cementing her role as a secondary team figure characterized by provocative self-display, unpredictable athletic input, and the impactful assault episode that fractures team cohesion.