Comes from the first time someone had sex on a quilt on top of a hardwood floor. It is the moment in which the person on bottom (usually female) begins to be scooted up across the floor. This can be used in more than one way; i.e. to swiffer, swiffered, to get swiffered.
Matthew: How was that swiffering last night?
John: Let's just say it was on wet vac.