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High school student Aoi Aioi lives with her elder sister, Akane, after a tragic accident took their parents away 13 years ago. Because Akane has since been taking care of her single-handedly, Aoi wants to move to Tokyo after her graduation to relieve her sister's burden and pursue a musical career, inspired by Akane's ex-boyfriend Shinnosuke "Shinno" Kanamuro. Shinno was part of a band until he left for Tokyo to become a professional bassist after the sisters' parents passed away, and he was never to be seen again. One afternoon, while Aoi practices her guitar in a guest house, she gets startled by the 18-year-old version of Shinno from 13 years ago! As if by coincidence, the current 31-year-old Shinno also returns to the town, but he has changed drastically. There are now two Shinno's in existence, but why is the Shinno from the past present?
She was born into a family of classical musicians, but Satsuki is the one misfit. She thought that she hated music; but, then, a prince with a guitar appears...?! “You are a genius DIVA!” That’s a lie, right–?!
Ari is a brand new first-year high school student. Shortly before school starts, she sees a band holding a mini outdoor concert. She is struck by how great the music is. That band, Sunnyside, is currently the hottest indie group. AND, the really cute lead singer, Youta-kun, is a student at Ari’s new school! Even better, he is in her grade, and they will be in the same class! However, Youta-kun is really popular with the girls, and he happily lets them hang all over him, like he's dating them all! Youta-kun becomes really interested in Ari’s piano playing and makes an instant decision - Ari must be Sunnyside’s new keyboardist!