There is something interesting here, but there was a lot that to be honest just left me annoyed. Cue: 
-love triangle 
-attractive best friend that we are NOT interested in
-main character that everyone says is "special" 
-young MC with skills no one else has 

I can take some of these but so many of them together is hard to take. The main character felt naive and I didn't feel a connection to any of the characters. 

The most interesting part was the witches/magic/world-building. I think the book would actually be much more interesting if

it was from River's perspective--infiltrating the court, finding out where the bones are, etc.

But I guess that wouldn't leave room for the "big twist."