Prostitution was common in the Middle Ages.
It’s mentioned dozens of times in both the Old and New Testaments of the Bible and recorded in the Western Zhou dynasty of China. The Mayans had brothels guarded by soldiers.
IMHO Casanova’s popularity was because he had a strong interest in satisfying women. Starting with genuine conversations. Rather than the Chauvinistic attitudes that were the norm at that time.
He probably learned to spend more time on foreplay and oral sex. Whatever he did apparently worked extremely well.
Casanova would probably be quite comfortable in todays world.
Is there any historical evidence that men finishing on a woman’s face was ever a popular move? I don’t recall any historical texts that ever allude to this and it seems to have been something wholly invented by the pornographic film industry which would make it a unique historical novelty.
Do we know if it’s popular now? I suspect it’s done in porn but rare in real life.
Lots of interesting answers, thanks. I particularly liked the article on Sex in the Middle Ages. This bit made me chuckle :
Now that you mention it, I read some Fabliaux about 10 years ago and, while I don’t remember much about the stories, I know I was rather amused by some really outlandish situations, such as a man having penises all over his body.
Yeah, it’s something I’ve always wondered about. I’ve never seen the appeal at all, and absolutely no woman I’ve know has ever asked for me to do this.
Just one thing. As I whote in the OP, I know that these practices existed then, and I’m sure that thousands of adventurous individuals experimented with various activities just like we do. I’m just wondering whether the average medieval man/woman had as broad a potential… repertoire as the average 2022 man/woman.
Also, I mentioned the Middle Ages but it could be any time or place.
I thought everyone knew how the Missionary position got its name.
Was it named by the Azzfukker Tribe from ancient Patagonia?
The famed Azzfukkers were only one out of hundreds of tribes globally whose adventurous sexual activities were curtailed by missionaries. So, asking if the “primitives” knew other positions outside the M is a prime ass-backward example of English disease.
As already commented, it seems doubtful that there have been any significant . . . uh, let’s say “innovations” in sexual behavior since ancient times
But it might be worth noting that today, in the Year of Our Lord 2022, it’s possible to find people who will profess disgust at any sexual activity outside of a married couple doing it in the missionary position, under a heavy blanket in the dark.
That’s a male-female married couple. Other legal marital pairings also exist and probably inspire negative feelings in those persons.
. . . through a hole in a sheet. . .
Seriously though, it is generally accepted that the fewer outside entertainments are available in a geographic area, the more randy the locals will turn out to be. The Canterbury Tales would seem to support this theory.
I’m currently on holiday in Greece. Based on the engravings on several artifacts I viewed in one of the many classical museums in Athens, your observation holds across most of the borders of antiquity. Seems that the people of today have an unearned patronizing attitude toward the people of the past.
This also reminds me, years ago, I saw a compilation of stag films made during the silent era. I recall thinking the only real distinction between the filmed sexual antics of 1920 versus today, beyond the superficial technical advancements in filmmaking, was the copious amount of body hair. Other than that, the positions, physical combinations, and even the camera angles were all basically the same.
Well, perhaps the heightened interest in the private habits of nuns was unusual. Especially when they brought in the little dog…
Reminds me of the story about Dillan, a young Welsh baptist who married his sweetheart on a Saturday. A few days later he went to see the minister. After much beating around the bush, he finally managed to ask the question that bothered him so much: “Is it allowed to make love on a Sunday?”
The minister said that he had never considered it and would have to consult with his superiors. The following Saturday, he called on Dillan and gave him the answer. “It’s all right to make love on Sundays,” he said. “So long as you don’t enjoy it.”
Sex was commonly euphemized as “The poor peoples’ opera” for a reason.
I am surprised we have gotten this far and no one has mentioned the Kama Sutra yet.
You isolate two human beings their entire lives and eventually put them together they will figure a lot of things out. Sexuality doesn’t have to be taught, it’s fairly inate, and adults are smart enough and curious enough to be very creative sexually.
Puritanical teachings may override or be a limiter on such ideas, but not necessarily.
What happens in Puritania, stays in Puritania.
More like what doesn’t happen in Puritania. 
My guess is that the OP’s time traveler is a white guy, especially since the OP refers to the Middle Ages which is a time period of high importance to Europeans.
Is that correct @Moonrise ?
If so it is very funny that a white time traveler has overcome the barriers of time, but is still geographically fixated on Europe 