The Zipper

A woman tried to board a bus but her skirt was so tight that she couldn't make the step up.
So she reached behind her, lowered her zipper and tried again. Still the skirt was too tight.

So again she reached behind her, lowered her zipper a little more and tried to negotiate the step, but still the skirt was too tight.

Determined to catch this bus, she once more reached behind her, lowered the zipper a little and attempted to climb aboard. Then suddenly she felt two hands on her butt, helping her on to the bus.

She turned around angrily and told the man behind her: "Sir, I don't know you' well enough for you to behave in such a manner."

The man replied: "Lady, I don't know you well enough for you to unzip my fly three times either!"