It's one of the best books I've ever read - a masterpiece of insight into the criminally insane mind - yet somehow very humourous. It might be sick and disturbing, but I think it really takes courage for someone to write something like that - it made me think it was "brutally honest" in that he didn't try and comfort the reader or leave out important scenes because they were disturbing. The characterisation was spot on - entirely (scarily) believable. I didn't think I'd enjoy it, but it was only a couple of hundred pages so it wouldn't take long, I started reading it and was utterly intrigued by it.