As you can see from the title of today's strip, this segment of the story arc actually did happen to someone, except that the events were slightly different. A friend of mine was dating this guy who was, regrettably, one of the sleaziest manwhores of all time (which she wasn't aware of, somehow, until after this sordid little event). At any rate, he was always pestering her to let him pay her a little "lip service", so to speak, in hopes that it'd get him closer to getting into her pants. Finally, after weeks and weeks of this, she said "yes" to shut him up. (keep in mind this was during high school, when most of us were still kind of freaked out by the whole sex "thing".)
...Well, she fell asleep. And no, he never noticed. To this day, the guy in question has no idea that she dozed off due to his lack of skills as a cunning linguist.