A wife was in bed

A wife was in bed with her lover when she heard her husband’s key in the door. “Stay where you are,” she said. “He’s so drunk he won’t even notice you’re in bed with me.”
the husband lurched into bed, but a few minutes later, through a drunken haze, he saw six feet sticking out at the end of the bed.

He turned to his wife: “Hey, there are six feet in this bed. There should only be four. What’s going on?”