We have a story that starts out similar to anusman's but is an audio rather than a visual one.
Back in about 2002 we went on a road trip holiday with a group of college friends. The group was 7 guys and 3 women, with myself and my lady the only couple. We were all students so we camped where possible. On one of our stops, in a city, we couldn't find anywhere to camp so we cheekily got a room (albeit with two beds and lots of floor space) at a very cheap hotel. It was in the style of US motels, in that all the room doors opened out to a courtyard.
Anyway, by this point time myself and the lady had been forced to 'behave' (because of never being alone) for about five days and we were both getting a bit desperate. We were out with the group in a club and she asked me if I thought I knew the way back to the hotel. I said I did so we made an excuse (she was tired, probably) and slipped away.
Back in the room and we were all over each other, in a hurry to relieve the frustration. We had left an hour before the club was due to finish so we figured we had at least that time. More than enough.
Moving the story on, when we got to the main event we discovered the bed in the room moved and thus banged off the wall. At first, she was bothered by this (as she would have been at home) but I said "Who cares?! We don't know anyone here!" and proceeded to increase the pace to make my point!
This, shall we say, took her mind off things and I guess she knew I was right. She's normally not very vocal - unless she's had a few drinks and that was the case this night. So again, since we neither knew nor cared about whoever might be in the next room, she really let herself go. She loudly praised me, my cock, how she loved fucking me and every time an orgasm was imminent. We basically turned into the neighbours from "The Secret of My Success"!
Eventually, I had my happy ending. We looked at the clock: still about 20 minutes left until we would have expected the others to return. As is her habit, the lady goes to the bathroom.
While she's in there, my own reverie is interrupted by a knock at the door! What's this? I throw on my boxers and open it a crack. It's one of our group, on his own.
"Hey man, come in. What's up?" I ask him.
"I need some extra money and I've left it here in my bag" he told me, adding that some of them decided they were going to go on to another club. Whilst the rest all had enough cash, he realised he was short.
"Did you just arrive back now?" I asked.
"Nah man" he said. "I've been out there for about 6 or 7 minutes but I knew better than to interrupt THAT."