This is a Victorian girl's finishing school story with a supernatural twist. Voya recommends it for 10-12 grade students. I agree with that evaluation. It is a somewhat challenging read, a longish book, and has some mature content although no explicit sex. However, all that being said, this is a book I am going to recommend to lots of students (and perhaps my daughter). It is complex and really delves deeply into the development of friendships between young girls and the temptations that many girls face.
I'm always looking for connections. It appears to be a good portrayal of Victorian girls schools and the era. It also begins in the British governed India. This is a book I listened to on my smart phone. There was a great surprise at the end--the author had a relatively long autobiography of the process she used to write the book including a trip to England for research. This alone is a wonderful addition. Young women reading may be motivated to consider sophisticated research for their writing projects.