This story is set in Japan. It stars a girl, Morino, and a boy who is sort of a friend to Morino. He is not named. They are classmates in the last year of high school. They are obsessed with serial killers and death. The boy tells part of the story in the first person. There are other narrators who tell their story in the first person. Morino is always shown through the eyes of others. The boy appears to be a psychopath. There are serial killers in the book. There is child and animal death. There is mutilation of people and animals. I found the book fascinating. I recommend this book for anyone who wants to read a very dark horror book that gets in the minds of some very disturbing individuals. If any of the issues I mentioned are a problem for you, you might want to pass on this book.