I don't often review sequels or books that aren't the first in a series, but I think that there are some readers to whom this book will appeal . . . but be warned: it's certainly not for everyone.
Mr. Monster is the second book in a horrifying series that starts with I Am Not a Serial Killer. John Wayne Cleaver is obsessed with serial killers, and he's also a diagnosed teen-aged sociopath. He already took care of one demon killer in Clayton County, though no one really knows the whole story (like the fact that the killer really was an actual demon, or the fact that John's the one that destroyed him). Now there is a new serial killer in town, and John craves details to help answer some of the essential questions: Are the two killers related? Who is the new killer? Why is he killing? Before long, many of John's questions are answered, but it may be too late. How can he hold onto his "John the Brave" reputation if he can't figure out how to NOT to die.
John lives in a mortuary -- which feeds, and also calms, his obsession with death -- and this series contains very graphic descriptions of embalming, along with murder, torture, and death. These books are meant for those with strong stomachs, but beyond the gross, the storytelling richly combines the genres of thriller, horror, and fantasy into a mystery at which you can't quite stop staring, long after each page is turned. As each professional and reader review points out, adult and teen fans of the TV series Dexter will love this.