I'd like to defend the prince (all of them?) even though I don't see me folowing this story. Bottom line is, her dad was a tyrant, she was also a terrible person. I'm not saying it justifies anything, but when a tyrant is taken down, everyone in his family line would be killed, right? Jax didn't kill her, because of his father's wish to let her live. I don't see him torturing her, she became a maid, and of course because of her lowered status, and because of previous actions by her and her father while she was still a princess, would not endear people to her. Also, if he just let her go, she had nothing and no one. Civilians nearly killed her when she appeared in front of them. If she's going to take back her rightful place, she will be undergoing a lot of humiliation and it'll be a struggle to get people to follow her.
The ml didn't personally kill her family, but he did support the rebellion against her father. It was mentioned in one chapter that he was hanged by his own slave?
But her position is already quite okay, she can rise up if she doesn't buckle under the struggle. In her current situation, not being left to the citizens who clearly want her head for her father's actions is already quite good, she might have been imprisoned or just killed, but then we wouldn't have a story. For the daughter of a fallen tyrant, she's in a better position than most I've seen because she's free to do whatever she wants. It would be one thing if the ml killed her parents for no reason, but I bet this was a plot by the uncle (current acting king of the north?) and the citizens were in full support because her dad wasn't a good king. So this part, it's not personal, it's politics, so I have nothing against him personally, but I just cant see this writing doing a good romance between the two of them justice. Because it is a nice idea, I read something with a similar premise and I was both happy, and not happy with how it ended (a man enslaved from kingdom A, the royal family of kingdom B is all trash besides one, the youngest. Prisoner humiliated, beaten up, barely given human rights. Since he lost his family he gets revenge and kills royal family of kingdom B, but had romantic developments with the youngest prince, who now becomes his slave but is treated way better. The kid knew his family was in the wrong so he couldn't even get angry. Prince A and prince B still end up together, but the resolution was too anticlimactic for me.)
I have read stories where the fl fell for the ml who took everything away from her that are mostly BS, but the idea does have potential (to be a really angsty, dramatic epic). But considering the material is Chinese, I hesitate to trust it since all their straight tories have the same tropes with fl and ml falling in love for no reason other than looks/riches.