I, for one, am not particularly surprised that kafka was into dirty stories.

More importantly, from the comments:

Kafka might have been a great Author of his time, but now it has been found that he was nothing but a pervert. For Edwins information, millions if not billions) of normal people do not indulge in porn, a small minority do as they can not get their kicks any other way.

o rly? This guy undoubtedly has some horrible, unspeakable fetish that he's trying to repress by pretending to be a puritan.