What does DDF mean hookup?

Excuse me, I'm a bit confused about a term I've come across recently. Could you please clarify what "DDF" stands for in the context of a "hookup"? I've seen it used in online dating profiles and personal ads, but I'm not entirely sure of its meaning. Is it some kind of acronym or slang term that's commonly used in the cryptocurrency or finance world? Or is it perhaps something more general that I'm simply not familiar with? I'd appreciate any insight you can provide.