Melting His Heart with Her Voice

Yuuki Masato was engaged to a person he knows, but didn't really expect it to be Nishikino Maki. Masato is such a rude guy but always tells the truth though he knows that no ones gonna believe him. Can Maki change his rude personality? How can µ's and A-Rise continue in musical industry if their new enemies are their composer's parents? OC x Maki (bad at giving summaries, sorry)