Although they truly love each other, Paul and Ellen have been struggling in their marriage. In this story they engage in a marathon sex session to get their act back together. If more people sat down -- er, laid down or bent over -- and engaged in this sort of therapy, we'd have a lot fewer broken marriages in the world.
My favorite pun in the whole story -- which I think is accidental -- is Ellen's question: "Are you sure nobody's going to come back here tonight?" Her concern is that somebody might find them copulating in the abandoned back room. However, when she asks the question, Paul is getting ready to ream out her asshole. Later, when Ellen gets "a fucking cramp," I think that pun is intentional.
Again -- my health caution. You really do have to be a little careful about anal sex. Germs from the front just don't have enemies in the back, and so you can get a nasty infection if you are not careful. In addition, KY is superior to Vaseline or to face cream, because of its water-based chemistry. You can actually get skin burns -- and learn to hate a pleasant activity --by doing anal sex wrong.