Magallanica's Mermaid Princess.TRY3 attends a special concert featuring Saya Yatomi, a popular idol from the Magallanica region and daughter of a former idol, Hitomi Kouzouji. They reluctantly become part of the event staff, and Tokoha finds herself fulfilling Saya's diva-like demands. Nonetheless, Tokoha realizes that she and Saya are alike in that they both want to be recognized as individuals and stop living in their idolized relatives' shadows. After a last-minute stage show in which Tokoha and Saya get in a pie fight, the two have a cardfight to settle the score. Then, when Chrono arrives home, he is told by his aunt Mikuru Shindou to stop playing Vanguard...