step-son's friend fuck his new step-mom while phone talking

I had just come home from work and there was a knock at the door. It was my step-son's friend. I let him wait for his friend at our place and went to take a shower myself. When I came back and made some tea I found out that they had recently been to a swing club. This really turned me on and when he went to wash up I got on all fours and waited for him.