It's S4. Ying Mengtingla refers to Sakuraba Rola, one of the heroines in The Star in Idol Activities. In the plot, she is a junior one student in a four-star college middle school, and in the second season, she is promoted to the second grade. Nijino Yume's classmate, currently the cadre of Hua Ge Tuan and the vice chairman of the new student union, is a powerful idol. In the plot, there are four protagonists: Yingla, Wei and Li Wei.