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After appearing in the Prism King Cup representing Edel Rose, and getting a glimpse of what it was like to a be a future Prism Star, Ichijo Shin entered Kakyoin Academy’s High School division in spring and became a first-year high school student. Koji, Hiro, and Kazuki from Over The Rainbow left Edel Rose and established a new agency. Meanwhile, after having the title of Prism King stolen by Hiro, the leader of Schwarz Rose, Norizuki Jin, proposes PRISM.1, which would decide a new king other than Prism King. He then announces that Schwarz Rose and Edel Rose will be competing with each other.
The members of Jupiter — Amagase Touma, Mitarai Shouta, and Ijuuin Hokuto — are aiming to be the best in the idol industry. As their concerts start selling out and their popularity increase, they experience issues.