I think I read this.
The cover looks familiar.
It’s the first book in a trilogy.
I think the main character is a rebellious daughter (princess) of the ruling family, with some sort of dark, unexpected, or late-blooming magical powers.
But… I can’t dredge up more than that from my memory.
It’s on my list of books to request again later, so maybe I will provide more detail in a few months.
Well, ah-ha. Here’s a review by another blogger – there are the trapped-gods in that bizarre castle.
That somewhat brings it better to mind. A fairly good book, after all. I just couldn’t connect it to the cover and title.