As a teenager myself, I find the idea of censoring books because of such subjects ridiculous. To begin with, as it has been mentioned above, sex, drugs and violence are everywhere, therefore being a teenager of a west civilization is a bit rare. These protests come from narrow-minded people who don't know what's going on around them most of the time, f.e. parents afraid of discussing sexuality when their kid may have already had sex. (this sentence may be a little disorganized, I hope it makes sense) Besides, personally I do some research and if a book I'm interested in contains themes I don't feel comfortable with, I'm not going to read it. F.e., I'm interested in reading The Lovely Bones, but I don't think I'm yet ready to read a graphic scene of rape.