With the arrival of a new generation of talented girls, another lively year at Seishou Music Academy begins. The graduating 99th class is already preparing for the much-anticipated rendition of Starlight, a bittersweet story about the parting of two girls.

It seems like all students in the Actor Training Department have their post-graduation future figured out—except for the cheerful Karen Aijou. Having fulfilled her promise of performing in a play with Hikari Kagura, her ambitious childhood friend, Karen struggles to find her purpose. What lies beyond their promise is a mystery to Karen, as Hikari was the fuel that kept her passion for performing aflame. Now alone, Karen must confront the reality of stage girls and find her way toward the future—her very own stage.