A young couple were making passionate love in the guy's van -- you know,
shag carpets, big double bed in the back, all of that -- and suddenly
the girl, being a bit on the kinky side, yells out, "Oh lover, whip me!
Please whip me!"  Well, the guy, not wanting to pass up an opportunity
like that, but unsure what to do as he has no whips around, gets an
inspired flash, opens one window, snaps the antenna off his van, and
proceeds to whip the girl until they both collapse in sado-masochistic
ecstasy.

Almost a week later the girl notices that the welts she sustained are
beginning to fester a bit and goes to her doctor.  The doctor takes one
look at the wounds and exclaims, "Wow!  Looks like you've got a bad case
of Vanaerial disease!"