Nonoyama Fuu - an innocent elementary school student very excited for Summer Vacation. Nonoyama Rui - a modest, hard-working Junior High School Student.
Two sisters that only recently have become distant from each other... One day, Fuu encountered a mysterious spaceship and received magical powers. Rui also had received magical powers. Fuu and Rui transform into the grown-up versions they wish to be. However, there are two rules: You will only have magical powers for one year and No one should know about your magical powers. The two of them did not know each other's secret! Each of them will become idols!

Source: Bandai Namco Filmworks

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