Ok. So there are plenty of cases where your scenario would work. A famous example off the top of my head would be The Great Gatsby. As long as you work out why you're following a different POV, it should work.

Also, I don't think it's weird that the king is a she, either. As long as it's explained in the narrative, that could work.

And lastly, there are a lot of ways you could write the story. And here's a little secret: the antagonist is the protagonist of their own story.

tldr: I think your idea would work. I would be interested in seeing how it would work.