This was made in response
I understand that; my point was that she had takers -- and (I'm pretty sure) she did not "perform" as (implicitly) promised. Which is OK in the sense that -- in my opinion -- promises shouldn't be legally enforceable, but nicely demonstrated that even when a woman straightforwardly offers participation in a sexual encounter, it doesn't mean anything... she could change her mind after, or even make the unambiguous offer while knowing well that she doesn't intend to follow through.
Before starting to walk with her toward the supposed place of assignment, I would demand a performance bond from her: she should give me a hundred bucks which she would get back after having sex with me -- and which I would keep if she reneged on her (implied) promise.
That would quickly make it apparent of what's going on.