Mio is searching for a method to make Pure Palette shine more than ever. At that time, Hibiki gets everyone to challenge Spa-Katsu. Spa-Katsu was harder than everyone could have imagined, it was a tough battle! Following that, it was revealed that the Friends group that Hibiki was previously in was!?

A newcomer idol, Wakaba is told to serve Aine as her "one day assistant". At the same time, an unpolished jewel appears before Aine......! Aine wants to show to Wakaba how senior she was, but she works hard with an "adult-like behavior" different from usual?