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This is the (imaginary) beginning story of the crazy popular Vocaloid Character GUMI!! By some freak incident, the now cyborg school girl has her eyes set on her idol debut as "Gumi" under the mysterious organization, "Intane Group"!?
Natsuki, a third-year at Sakuragaoka High School, holds unrequited feelings for her childhood friend, Yuu, who’s in the Film Club. However, instead of being honest about her feelings, she makes him her confession “rehearsal” partner. Unable to say her true feelings, things start to get complicated when Miou and Akari, who are also in the Art Club, get involved! Will she ever be able to confess for real!?
This is the last time I’m going to practice… Natsuki Enomoto, a third-year student at Sakuragaoka High School, has feelings of unrequited love for her childhood friend, Yuu Setoguchi. Unable to be true to her own feelings, Natsuki tells Yuu that she is merely using him as a stand-in to practice confessing her love to. As Natsuki continues to pretend not having any feelings for Yuu, her classmate Koyuki Ayase asks her out on a date. Will Natsuki ever be able to stop “practicing” and actually confess her love to Yuu?