This book is about two sisters and the strong bond shared between them. One was missing, meanwhile the other was trying to save humanity from earth's destruction.

I doubt I have the capability to phrase my amazement of this book right now. It's just so different from what I am used to, as I haven't read many sci-fi books to compare with, and I was drawn into it almost immediately. It made me think, "to what extent would you sacrifice for the sake of others? For humanity?" This book was painful and gave me so many new perspective of life. Now excuse me while I stare at the ceiling, cry, and absorb what I had learnt from it.