George and Anne are a happily married couple, in their mid-thirties. Their sex life at home is satisfying. They have one son, Kevin, who is 10, and until recently spent one weekend a month at with his grandparents. Although George's parents could still take their Kevin over the weekend, Anne's mother had passed last year from a sudden stroke at the age of fifty-eight, leaving her father a widow and they did not want to put the pressure of watching his grandson alone on him. The reason for their son to stay weekends with their parents was that George and Anne had enjoyed going to swinger and sex clubs for...