Superman was flying over the skyscapers of New York when he looks down and sees superwoman lying down on top of one of the buildings. So he thinks to himself 'I'm so fast that I can fly down to her, give her a good shagging and fly off again in a split second' So this is what he does........
A second or so later Superwoman shouts 'what was that?' and the invisible man screams 'F*ck knows, but me arse hurts'