The narrative unfolds across two magical islands, Harmony and Cat Island, and is told from the perspectives of the heroines Kahoko Hino and Kanade Kohinata.
Kahoko Hino: Called to "Harmony," an island where a musical fairy named Fata resides.
Kanade Kohinata: Transported to Cat Island, a smaller, uninhabited island near Harmony.
Both heroines must uncover why they were summoned to these islands and work to return to their own world while addressing the crisis threatening the fairies’ islands.
Teaming up with musicians from different eras, they rely on the power of music to forge new bonds and save the magical islands.