Before she met me my wife had several threesomes, of various kinds. She's very bisexual (basically she just loves sex) and so arranged for a threesome with a couple who she found attractive. She got up to the bedroom, they all stripped and began foreplay. But the female half decided she didn't want to go through with it. She left the room leaving my wife and the male half of the couple. They shrugged and carried on with it because they both horny as fuck. The guy made a lot of noise while fucking, effectively cuckolding his wife in a different room. My wife says it was very hot to fuck somebody's partner while they were so nearby although it was a shame she didn't get to lick pussy.