Here are a couple of books are on my radar that are clearly NOT for kids.

All My Friends Are Dead
Published by Chronicle Books, this is the funniest sad book I’ve ever read and the saddest funniest book.

Go the F**K to Sleep by Adam Mansbach
I’m still giggling.

Check out this article on how the free PDF drove the book to #1 on Amazon well before its publication date.
http://www.baycitizen.org/books/story/go-f-sleep-case-viral-pdf/