The characters aren't especially unlikable- except for the ex boyfriend who is one of those completely irredeemable dicks that I can't bring myself to care about because the author didn't put a lot of effort into him.
The main character herself doesn't really seem to have much of a say on her own life and just when you think she will, it turns out her fake fiance is manipulative and kind of evil. The explanation as to why her father wasn't in her life for twenty years is perhaps the worst one I've ever seen.
As for the story itself, I'm not too fond of the pure revenge trope because it's limiting and leans heavily on the reader's sense of justice and internal vindictiveness than any good plot or characters. Getting revenge as a side quest to something more fulfilling is much more satisfying to me and opens more doors for a good story, but single minded obession gets old quick.
Lastly, the art itself isn't bad but the artist can't really capture full body motion. Sword fighting or combat especially looks stiff and doesn't flow well. The way the dresses fall looks stagnant but the facial features are well done.
Also everyone is two faced for some reason, as in no one is really who they present themselves to be. This manhwa isn't bad per se, but I personally don't like main characters who are led around by other characters or are ruled by emotion. This entire thing just isn't for me.