From a very young age, under the guidance and teaching of his mother, Arima Kousei (voiced by Hanae Natsuki) regarded becoming an excellent pianist as his lifelong ideal, and along the way, he also achieved many good results. Unfortunately, at the age of 11, Arima's mother passed away, and Arima could no longer hear the sound of the piano he played, so he gradually drifted away from his original dream. In the third year of junior high school, a girl named Miyazono Kaoru (voiced by Taneda Risa) appeared next to Arima, and Kaoru played the violin. Soon, Arima was attracted by the talent and enthusiasm exuded by Kaoru. What Arima didn't expect was that Kaoru actually designated Arima as her accompaniment in the competition. Under the influence of Kaoru, Arima gradually rekindled his love for the piano, and the distance between him and Kaoru became closer and closer.