Tsubaki's been Kousei's childhood friend forever—she's basically been his biggest cheerleader, showing up to all his piano performances. Back when they were kids, she'd try dragging him outside to play, but his mom's relentless practice schedule always got in the way. Over the years, their dynamic settled into something like older sister and annoying little brother, with Tsubaki naturally falling into the caretaker role.
She's not a musician like Kousei. Instead, she's the athletic type—played softball through both middle school and high school, and genuinely loved the sport. She kept playing alongside some senpai from her middle school days.
Content compiled by AnimeList.moe from publicly available sources.
