Zoo by Otsuichi

Damn, what a twisted book! The writing is nothing special, and some it is downright bad (not sure whether to blame the original Japanese author, or the translator), but the stories are awesome. One I've read so far really got to me. It's about this dude who is abused as a kid. He moves into a forest where he builds a house out of the bodies of people he murders. It's really messed up. Another story is about a guy who gets stabbed. However, he can't feel any pain. And so he's bleeding to death while his POS family stands around arguing about how long it'll take him to die, or who will get his inheritance, the last night's dessert, and other such nonsense.

I really want to see the anime anthology based on this; I bet it's pretty good.