Watching your wife suck other people's dicks is a buzz kill. And she understands that by licking other people's testicles, her husband's boner will get sharper. So these swinger couples swap to sharpen their senses, bring back the novelty, and make their orgasms brighter. Only I would make the lighting not so bright, then there would be more understatement and less embarrassment.
Turns out the buyer and the girl have so much in common - they're both from Canada and even from the same city. As it turns out, they even have mutual acquaintances! Then they moved on to memories of sex parties in their college days. How could such a momentous meeting go without sex? The girl was so turned on that she didn't mind communicating with his cock closer. Lucky for the man. ))
Actually, computer science is on Wednesday.