Your Lie in April
Kaori is Tsubaki's classmate. She plays the violin. The judges for music competitions don't like her playing (because she does not play what is written on the sheet music) but the audience likes her playing. Kaori met Kōsei when she first met up with Watari. She helps Kōsei play the piano again. At the end of the anime, it is shown that she liked Kōsei, not Watari.