The main premise of CFNM porn is that there are a naked man and a clothed female. This way, female maintains her dominance over a weaker man, keeping her clothes on while forcing him to strip naked and obey her commands wherever they are. Nude men are there for the pleasure of these clothed females and they will toy with them any way they see fit. She might want to humiliate him outside or in a public place, or just want to play with his cock for fun, so he will strip naked and she will keep her clothes on for as long as she likes.