Let me start by saying I loved the world that these authors have created, and the story itself wasn't bad, but I found that I had to constantly remind myself that the main characters were supposed to be 18 and 21.
From the language the characters used and the way they acted, they seemed much younger, perhaps 15-16.
So when in the last couple of chapters when the characters showed more mature behaviours and feelings, it was quite jarring.
I also found some of the events broke the immersion of the world, in that even in this fantasy world that the authors have created, I struggle to believe this would happen (I won't give examples for spoiler reasons)
All in all is wasn't a bad book, and I will probably read the second in the series, but I'm not sure I would recommend it to friends.
At least not based off this first book.