Tong Ye is the star dan performer of a Peking opera troupe. His best role is Yu Ji in Farewell My Concubine, and he seems to have lived his entire life inside a play.
[Blurb One]
In a different play, Yu Ji hasn't taken her own life yet, but the King of Chu has already gone ahead and died. Even more absurdly, Liu Bang has become the "King of Chu."
[Blurb Two]
When the "uninvited guests" truly break into his home, the Peking opera stage in Beiping is gone, the troupe has scattered, and Tong Ye becomes an underground Communist Party member. During an operation, he reunites with the most important person in his life, Guanyue Zhou. This time, they are both lovers and enemies.
The protagonist on the righteous side is rather hot-tempered, straightforward, a little sharp-tongued, but sensible. The protagonist on the villain's side is gentle, the smiling, squinty-eyed sort. When he stops smiling, something is wrong. He's also very rational and shameless.
It's probably a story where one of the protagonists is a villain.
Also: Guanyue Zhou is an officer of an island nation. He couldn't possibly have never killed Chinese people, but he's fairly rational. He has to atone for his own crimes.
I will never regret being Chinese!
Since this is a tragic ending, you can consider it a story with no romance.
Please heed the content warnings.
Theme: Never forget the humiliation our nation has suffered