Kanata's little sister, Haruka, is a school idol at Shinonome Academy and comes to visit Kanata at her club one day. The sisters are very close, but Haruka is worried that Kanata is pushing herself too hard and makes a drastic decision.

The Nijigasaki High School Idol Club is invited to perform as school idols at Diver Fest. But there's just one catch... Each school participating will only be able to perform one song.

The day of the School Idol Festival is finally here. Will everything go according to plan?