Kosei Arima - a boy who professionally played piano, won all children's competitions, his name was known to all novice musicians. Mother Kosei was his teacher. After she died unexpectedly, Kosei had a nervous breakdown during the performance, as a result of which he could no longer feel the music, despite the fine hearing and great talent. A few years later Kosey still did not touch the piano; the world seems to him gray and monotonous. He is glad that he still has good friends such as Tsubaki and Watari. One day he meets a girl named Kaori }, a talented and spirit-free violinist, whose style of play reflects her personality and soul. Kaori wants to help Kosei return to the music world and feel the music again ...