Sore wa Iromeku Fukyouwaon It's a Colorful Discord

Synopsis

Watanabe Soichiro is a cowardly boy with a bad temper. He enrolls in the Piano Department of Meisei Gakuen to play the piano, his only skill. Soichiro wanted to live a quiet high school life, but was spotted by a piano-obsessed female student named Otsune Fujioka. However, thanks to her support, Soichiro got a chance to play the piano in public. That day, Soichiro was in front of a large audience!? (Source: Kadokawa, translated)