Previous relationships I developed a kink and liking of sharing my woman with other men.. (Gloryholes/Sharing/Creampied and Returned)

I brought it up to my current wife when we first started dating and that I still like that style but only if she’s comfortable with it

Before I could say anything else she shut it down and wants to be with only me (which I respect love her wishes)

But the part that gets my eyebrow raised is somewhat recent, she said she’s had a fantasy of getting off the delivery guy or fucking/sucking the delivery guy (Pizza Guy/Mailman/Milkman/FedEx/Amazon/etc.) And I want to push that boundary, see what she has in mind.. but at the same time I know it’s most likely gonna get shot down…

How would you approach her/the situation.. to ease her into letting a stranger dressed like the delivery guy (that is drug and disease free with or without condom) into having her mess with him while I’m “out running errands” or upstairs “sleeping”