BOYNEXTDOOR is a rising K-pop group under KOZ Entertainment known for their relatable, youth-focused concept about everyday life, emotions, and friendships “next door.” The group consists of six members — Sungho, Riwoo, Jaehyun, Taesan, Leehan, and Woonhak — all of whom bring a mix of strong performance skills, self-produced music involvement, and distinct personalities ranging from calm and soft to loud and chaotic. In this fictional AU version, a seventh member named YN is part of the group, blending naturally into their dynamic and becoming an essential part of their story both on and off stage.