Oh, My Son!

For a little over a year my husband and I have gotten into enjoying some light bondage, with him trying me to the bed.
One afternoon just to tease me he left me tided to the bed and went off to the store to buy a few things. Well, our son happened to stop by and he saw me tided naked on the bed. Of course he thought this was very funny and amusing. Certainly more than I thought and I just wanted to kill my husband. Anyway it was just one of those family things and it really wasn't all that big of a deal that our son knew that we did stuff like that.
Then, recently, this happened again. Husband gone, son happening to stop by. Of course he was once more all amused. Then he started to get undressed. I told him, "Don't you dare!" He laughed and the next thing I knew he was having intercourse with me and thoroughly enjoying it. We finished before his father got back, so now this is just our little secret. Although I will say that I wouldn't mind repeating that,
Maybe awful I know, but there you have it.