Kemono no You ni Ueteiru

"I'm gonna make the funk music I love popular." This was once Aida's resolution, but time slipped by, leading to an ordinary career instead. Now, with each passing day, the sensation of being trapped continues to torment him. In the midst of this, a former bandmate extends an invitation. And when Aida takes up his bass guitar for the first time in a long while, sure enough, his heart trembles to the music...

(Source: MANGA Plus)