And what is with the strange girl that he sees everywhere?
It was pretty hard to do a summary of this book (as seen by the terrible attempt above) because this book is centered on Yuuta and his state of mind. The plot itself is pretty simple: Yuuta is in a hospital for most of the book. To describe more would be to give the story away.
What I liked about this book was its atmosphere. The sense that something is wrong is very heavy, and the oddness of the things that Yuuta goes through is contrasted with the mundane hospital life where he does nothing but sleep and meet with few visitors. Nothing is what it seems, and I was left wondering how unreliable a narrator Yuuta was.
I can't say that I fully understand the ending of the book, but I have a rough idea. Plus, it was creepy and fit in perfectly with the atmosphere that the entire story had. To be honest, I'm hoping for a sequel which explores this version of Japan a little bit more because I have so many questions that are left unanswered.