Sometimes, Sunday morning after sex, I make Laura a cup of coffee and me a cup of tea, and we sit across from each other sipping our drinks and staring at each other, remembering how good it was to be in each other’s arms, and after a while one of us gets up, and the other follows, and back to bed we go.

This Sunday started out pretty much the same. Laura and I had some lovely good morning sex. I made coffee for her and tea for me, and we sat across from each other sipping our tea. Laura got up, and I thought we’d go back to bed as usual. “I’m going to the gym,” she said.

I must have had a sad look on my face. “What’s wrong?” she asked.

“You could get more exercise in bed,” I said.

“I know,” she answered, “but I have this monthly membership, and you know how you’re always figuring how much it cost per session. Thirty dollars divided by eight visits is four fifty a visit, or whatever it is. So the more I go the less per visit. Smart of me, right? While I’m gone you could go running or take a shower or something.” And off she went.