I have heard this book highly praised and moderately praised. I regret to say that I cannot praise it at all.
In the first place, the book is supposedly set in Victorian England. The scene is skilfully set, but the characters' voices, motivations, and concerns felt overwhelmingly modern. Gemma, with her unconventional background, could get away with it a bit, but four or five characters (all the ones we really get to know) having the same issue? It doesn't work. This is not a problem only with this book, however. It is sadly present throughout most historical fiction/historical fantasy.
In the second place, I quite honestly detested Felicity and Pippa. I think we're supposed to like them or feel sympathy for them by the end of the book, but I didn't. I don't see why I should. They were cruel, petty, and selfish.
And finally, the romance did not work for me at all. There was no substance behind it. It was all scandalous dreams and misunderstandings. I know that this is the first book of a trilogy, so perhaps Bray wanted to save that part for later on, but, like Felicity and Pippa, the romance failed to convince me to care.
Also, a strong content advisory here.* I finished reading, but I won't re-read it and I don't plan to read the rest of the trilogy. I just don't care what happens to Gemma or the others.
*I have read other books with somewhat scandalous content which didn't bother me nearly as much. I'm not sure why this did so much. I think it might be that, again, the romance had no substance.