Cheating Couple

The young couple was engaged in a most affectionate embrace when there came the sound of a key in the front door.
The young lady broke away at once, eyes wide with alarm. “Heavens,” she cried, “it’s my husband! Quick, jump out the window.”
The young man, equally alarmed, made a quick step toward the window, then demurred. “I can’t,” he said, “we’re on the thirteenth floor.”
“For heaven’s sake,” cried the young lady in exasperation, “It’s not a good time to be superstitious!”