Pretty girl...
I also do not get the NN genre. If you thought there was lots of free porn, that pales in comparison to how much NN content there is - basically everything outside of the porn umbrella.
I've heard that the concept is the viewers want to use their imagination...I'm guessing that they probably would have to, since if that is what gets them off, they probably are never going to see a naked girl in person unless they go to a strip club.
ADG