Four castaways, three guys and a woman ended up on an island somewhere in the sea. Prospects of being saved weren't very good so the men told the woman they need to deal with their "urges". They agreed to let one man have her on Monday, one on Tuesday and one on Wednesday and the rest of the week she's "off duty".
That went really great for a couple of years, until the woman died one day. Now the men were having kind of a problem. The first week they managed, the second week it got very hard and the third week they finally decided to bury her.