Yume no Hajimari. Yume Nijino and her friend Koharu Nanakura, who want to join the top idol group S4, enroll at the idol school Yotsuboshi Academy, where the four members of S4; Hime Shiratori, Yozora Kasumi, Yuzu Nikaidou, and Tsubasa Kisaragi, study. After her first class, where she meets homeroom teacher Anna Hibiki and a peculiar classmate named Rola Sakuraba, Yume goes with Koharu to the Dress Make Room, where they make their own dress cards. While trying to see off Hime, Yume winds up in the boys' section of the Academy, encountering a boy named Subaru Yuuki. The next day, as the new students are brought in to perform a concert in front of their upperclassmen, Yume manages to give an impressive performance that catches the attention of S4, but suddenly collapses immediately afterwards. Waking up in the infirmary, Yume is greeted by Hime, having seemingly no memory of her performance.