Kyou Nekozaki attends the same high school as the series' main characters. She possesses long black hair with short bangs and typically wears the school uniform without the ribbon. Standing 166 cm tall, she is slightly taller than her close friend Shikimori.

Her personality radiates high energy, optimism, and outgoingness. She approaches others without hesitation, forms friendships easily, expresses emotions intensely, and cries readily. She enjoys popularity within the school and is often perceived as cool by her peers.

During childhood, Nekozaki struggled to maintain friendships lasting longer than one year. This changed when she befriended Kamiya, who became her first enduring friendship before high school. They play volleyball together on the school team.

Her closest high school friendships are with Shikimori and Yui Hachimitsu. Nekozaki actively strengthens bonds within their group, notably reaching out to integrate Kamiya into their social circle. She consistently supports her friends, encouraging the reluctant Hachimitsu during athletic events and celebrating her achievements.

Nekozaki frequently expresses admiration for other girls, particularly Shikimori, often commenting on their attractiveness, contributing to perceptions of homoromantic undertones. She exhibits tomboyish qualities through her athleticism, energetic demeanor, and straightforward communication.

Her development includes facilitating Kamiya's reconciliation with Shikimori regarding their mutual romantic feelings toward Izumi, which helps normalize Kamiya's presence in their friend group. Nekozaki remains consistently engaged in group activities, celebrating collective achievements like the mixed relay victory during the athletics festival alongside Izumi, Shikimori, Hachimitsu, and Inuzuka.