I have rather a bit embarassing story.
I was in Munich in February with many students from 3 countries. I made good friends with a guy, and one day he invited me to their room to play cards. There was his gf too. After a bit (to be exact, 4 hours) of playing I said bye and left their room. Others were talking on the corridor, so I also sat down and joined the conversation. (It was 3am just to say) After 20 minutes the guy's girlfriend left the room, went through us and entered her own room. The other sitting on the corridor were all looking at me and "Whoaa Beni, what did you TWO do there?"
Since they didn't know there was a third guy there and that we were playing cards, the thought we had -EXPLICIT CONTENT-. It was veery emberassing for me, although I swear nothing bad happened there. We were playing cards and she was chatting on her phone