Gimai Seikatsu - Days With My Step Sister - Chapter 6:

It wasn’t even malicious criticism.I just gave feedback in the tone I was asked to.So why the hell did I, the writer who just wanted to help a junior, possess this body of the prospective groom… a villain, who died in the hands of the heroine on their wedding night?

Dropped

30 year old Lu Ziwen was born in poverty and after struggling for a lifetime, he is finally able to perform in the Golden Hall symbolizing the highest honor. However, an hour before taking the stage, he was killed by his lover.

With eyes opened once more, he was unexpectedly born again in the body of the fallen star Qi Mu!

Who controls the world with notes?

Who is the king of the classics?

Qi Mu: I’ve conquered you; I am the king of classical music!

Min Chen: … As long as you are happy.

This is a story of a reborn violinist, vengeance, struggling for the top, and dominating the world of classical music!

- Description from Novelupdates

The countries of Mephius and Garbera have been waging a war for ten years and are trying to put an end to this long fight through a political marriage between the two royal families. Orba, who was driven from his home because of the war and was forced to become a gladiator, looks exactly like the crown prince of Mephius, and it has been decided he will be substituting him during the wedding ceremony. On the other hand, Vileena, the princess of Garbera, has secretly decided to ensnare the crown prince for her own country’s interests.