Frankly I don't see the need or a reason for that - one side is friends and family and the likes, and sex and porn is the other side (of my interests and interactions). Why should I mix these concepts? There are some regulars who I meet here and there for sex - but getting closer to them? That would feel more like a relationship than a friendship as far as I'm concerned.

I think we have different concepts of friendships. Not judging, just stating.