Hikari is a young school girl who dreams of becoming a great champion in the sport of rhythmic gymnastics like her idol, Diliana Gueorguiva. Despite all her setbacks while performing, she works hard and with the help and support of Takaaki Oiishi (the best male gymnast of her school) soon becomes a member of the rhythmic gymnastics team in her school. She develops feelings for Oiishi, but she is not the only one—Hazuki Shiina, the best gymnast in the entire school, also has feelings for Oiishi. Soon a friendship between Hikari and Shiina develops, but also a rivalry as well in the sport and for the love of Oiishi. Hikari is also torn between her feelings for Oiishi and her conflicting feelings for Mao Natsukawa, an old childhood friend, who is also the lead singer of the band called Mr. D. He composes the music she uses while performing, and has been developing feelings for her since childhood.

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