Every couple of months my wife and her best friend get together for a girls night.
I usually leave them alone for a few hours so they can do their girl talk and catch up, and then later in the evening I join them for some drinking and maybe cards. My wife knows that as a general rule I will try to shift things to a stripping game at some point, and most of the time she rolls her eyes or even specifically discourages me from steering things in that direction. But every once in a while, I sense an opportunity to go there. The signal I have learned to pick up on is whether the girls ask me to make shots for them. If they do, there is a pretty good chance that the evening will get interesting.
Story 1:
About a year ago, we had one of those opportunities and we started playing a card game and the girls asked me to make some shots. I did so, and we all drank together. Apparently the concoction I created was especially tasty and so they asked me to make another round, which I happily did. After an evening of drinking and a couple shots I suggested that we make the game more interesting, and to my surprise they were both up for it.