I remember this book surprisingly well, not like I read it yesterday, but that's what we have to make do with. The content itself is extremely appealing, but the cover is very nice and anyway it is about a dystopian world, who wouldn't get in?

Wren was a very sympathetic character to me; she was unfeeling, proud and infinitely stubborn, obedient, until we got to know her better, where her rebellious, caring and compassionate nature surfaced. It was a bit like a blazing fire surrounded by huge ice (I know it's a bit of a strange composition, but it doesn't matter). Callum was very cute, everything Wren didn't at first; he is kind-hearted, compassionate and understanding. I loved him with all my heart. 

I don't fully remember the plot, but I do know that it was full of action that made it all so fast. There was an interesting worldbuilding, not entirely unique, but imaginative and creative. I don't know how it ended up, but if I guess correctly, there was a twist in it.