Who is the real you? The "Tasokare Hotel" exists in a state of twilight limbo, allowing souls caught between the afterlife and the world of the living to rest. Neko Tsukahara arrives with no memory of who she is or how she came to be there, and is shown to a room filled with items relating to her past. As she searches for a way to remember who she was, a certain incident confronts her.

After surviving the entrance exams, Sakuta Azusagawa has finally enrolled in the same university as his girlfriend, Mai Sakurajima. He is gradually getting used to the unfamiliar environment as he attends student gatherings and makes new acquaintances. Everything seems to be going smoothly until Sakuta's friend and Sweet Bullet idol group member Uzuki Hirokawa begins acting out. With fellow Sweet Bullet member Nodoka Toyohama pleading for his help, Sakuta realizes that he has stumbled upon another case of the inexplicable Puberty Syndrome-Uzuki is feeling pressured by the sudden surge of popularity and rumors of a potential solo career. While Sakuta searches for a solution, another occurrence of Puberty Syndrome gradually emerges from the shadows.