How to Do It I’m shocked by what he said. Photo illustration by Slate. Photo by Getty Images Plus. How to Do It is Slate’s sex advice column.  Have a question?  Send it to Stoya and Rich here.  It’s anonymous! Dear How to Do It, I recently went on a girls’ trip with a few girlfriends from college, and we went out one of the nights. Most of us are in relationships, but a few of our friends are single, and they were interested in meeting people while we were out for the night. Not for a full-blown hookup, but for something more akin to a dance floor make-out. One of our friends was pretty heavily striking out (and we were all pretty drunk), so one of our friends in a relationship was like, “Here, I’ll kiss you!” And they kissed pretty briefly; it was all in good fun, and we moved on. I was relaying the story to my boyfriend in a sort of can you believe that happened way, and he offhandedly said, “I wouldn’t care if you had kissed your friends on the trip.” I was pretty shocked by this!…