shit, I was hoping nobody would do this.
there are two acronym ways of doing it - what you just said and also the "for unlawful carnal knowledge" - both of which are wrong.
people claim that they are middle age legal terms, but acronyms weren't around back then b/c for those to work you has to be a higher level of literacy... and there wasn't until far more recently.
the real origination is from "fokken" which is like danish or latin or some shit and means "to pump" I think.
in fact, one of the muslce magazines (don't recall which one) even had an article on this.
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