It's not that there aren't women interested in casual hookups, it's that the ratio of women who are, to men who are, make for not much better than lottery odds for men. A woman who is "interested"... and I put this in quotes because for a woman, interest doesn't really come into it.. if we want it, it's there, and an "interest" doesn't need to develop... and young women 18-23 simply haven't yet entirely discovered how this works in their favor! But they figure it out quick enough, with everyone banging on their door..
Chris Rock once explained this dynamic with
.
I think Tinder is about as close as you're gonna get though, without involving, er,
professional women. I'd certainly recommend being indicative about your intentions, unless you want to waste time entertaining the hopes of girls interested in a relationship which it sounds like you don't.
Just describe yourself as dynamic, and carefree, and always looking for new experiences, stuff like that. We'll know what you mean.