This happened on New Year’s Eve. We were in Colorado staying in the same hotel room (two beds) because it was only for three nights, and we figured it would be a good way to cut costs. We all got pretty liquored up at the bars that night, and kept drinking a little more when we got back to our room. I don’t even really know what provoked it, but my wife and I started making out, and then my sister and her husband started making out on their bed. One thing led to another, and about 15 minutes later all of us were having sex on our respective beds. It was a weird feeling, but weird in a good way if that makes sense, like a naughty thrill. I had that really excited butterflies in my stomach feeling and my wife whispered to me that she did too. We both really liked the taboo excitement of the whole thing, and I guess they probably did too. My wife still brings it up from time to time and says she hopes we can repeat it sometime lol.