鳴沢 律佳

Ryousuke's classmate who sits next to him. Her mother is a famous pianist, and she is also pretty skilled at playing the piano. Instead of socializing, she plays the piano in the music room every day. 

She and her younger sister Meguru both aimed to become professional pianists when they were young, but later it became clear that Meguru had talent while Rikka didn't, so she gave up on that dream. After Meguru was accepted into a music school in Salzburg, her family moved there, but she decided to stay behind in Japan, and has been living alone ever since./