I don't even know if I can explain why I love this book so much. What I will say is that if, like me, you keep seeing this around and thinking it's probably not for you, and that it looks on the young side, don't repeat my mistake and put it off. This book is absolutely worth picking up.

First person POV is often a miss for me, because I think it's overused and it can make for writing that feels lazy in the exploration of emotions. But I loved Cara's voice so much. I love the way she looks at the world, her determination to survive against all odds, the care she shows the people that she loves and thinks of as family, how brilliant she is. The world and the setting are fantastic too, don't get me wrong, but Cara makes the book work for me. 

The idea of there being multiple parallel universes, and that travel between them is possible only if your doppelganger on that world is dead, is such a fantastic premise. Learning about the different earths made me want to read more books set in them. I felt like I got to know all the characters so well that I wanted to follow their other versions. But this setup is also a great way for the author to explore the dark side of humanity. The story deals with themes of classism, racism, and how capitalism and power can turn people into monsters if they're not careful. It's not a light read, but utterly engrossing.