Some themes.

The protagonist is a young woman, so sometimes the "themes" - if there are any - encountered reflect that. Her world is not one that values the feminine, or otherwise puts femininity into a neat apron and leaves it at that, and so having a character with as much potential and power as Alexandra diCourtne does threaten some elements of her world. As a girl and as a woman, even as powerful as she is, her society places her in a more subservient position. Princesses might believe the best in everyone, but they need to be saved. And so on.

This is also explored through some of the other protagonists: Darius, for example, seems like a typical knight. He grew up from a modest family that kept an inn, and wanted to be like the knights in the stories he had read: honor, duty, bravery. Traits that boys were encouraged to exhibit. That his Lady could potentially be the young girl he had been friends with since childhood, and he could make sure she would come to no harm.

And then he realized that while his ideals were great and all - they were ideals. And what happens when the good hearted knight who wanted to protect others, becomes helpless? What happens when in order to keep him alive, a monster made him into something not quite human anymore?

Sketch of Darius.