Five men and one woman wash up on a desert island after a shipwreck.
Before long they are all getting pretty horny so they all make a deal. Each man will marry the woman for one week at a time, at which point the next man in line will marry her and so on.
All the men get sex every five weeks and the woman gets sex as often as she wants with a different man each week.
The situation works wonderfully for five years. When the woman suddenly dies...
The first week after wasn't too bad. The second week was geting sort of bad. The third week was getting pretty bad. The fourth week was really bad. The fifth week was horrible! By the sixth week it was unbearable... so they buried her.