Paraphrasing Frasier:
Niles: “There’s a man in my therapy group who claims to have slept with over 1000 women! Like 7 isn’t enough?”
Frasier: “I would have said 9, but I take your point.”
Frasier slept with 57 different women during the show’s run.
Plenty of wonderful friction can take place fully clothed.
Or swingers – happily committed couples who enjoy hooking up with other like-minded couples and/or group scenes. Definitely qualifies as “atypical” but doesn’t fit either of your scenarios above.
Or people in “open marriages”. The list isn’t meant to be exhaustive.
I think “Sitcom single” is different from IRL single. On TV and in movies, single characters always sort of presented as constantly meeting random attractive (if often annoying or otherwise unsuitable) age-appropriate dating partners. As the partners tend to only last a few episodes, a single character can rack up some series numbers over time. Even George Costanza has been with 47 women over Seinfeld’s run.
Mathematically, the answer is:
TheNumberOfPeopleYouFeelLikeYouCanMeetBeforeFeelingTooOldToStillBeSingle / e
If you feel like you should be married before, at least, 30 and can date maybe 1-2 people per year, at maximum then - starting at 18 - you’ve got about 18 potential people to date. But, once you’ve dated about 6-7 of them, you should pick the next person that you met better than everyone you’ve already dated.
(In reality, you might still be able to go back to earlier candidates, however, so we can probably outperform the mathematical result by a little bit.)
Just like Baseball. 
I will point out that the number of sexual partners a person has is a complex number. (It has a real part and an imaginary part.)
I re-ran the numbers and found an error. It actually looks like it will take you at least 230 years before you are likely to meet someone who will have sex with you.
And you knew that they’d had “many” partners how? They told you, or other prople spread the rumor?
And you know this reputation was “well-earned” how? You witnessed all these encounters?
Or so they claimed.
It’s always frustrated me that women get categorized as “sluts” based not on how many sexual partners they’ve had, but how many men have claimed to have sex with them. In truth, neither number should matter. There’s no such thing as a “slut.” There are merely people, both men and women, who have had more sexual partners than others. Why that deserves a derogatory term is beyond me.
Bravo
I’m not sure if there is a right answer. If one is hygienic and safe and honest with the people in his or her life there is definitely a wide range that could be considered reasonable. Not expecting society or others to make a judgement on that behavior is unrealistic however. Especially since so-called society has no hesitation to make a judgement on activities far less consequential.
Happily married so, in my case, that works out just fine so far as other potential candidates are concerned.
You’re my new hero !
Isn’t that sort of the point of this thread?
I suppose in theory, the number of sex partners a person has shouldn’t matter any more than the number of people they have coffee with. Of course, we would think it was pretty weird if someone sat in Starbucks all day looking to have a cup of coffee with everyone who walked in the place.
n+1
Why is this even a question? Any number is reasonable, unless it is interfering with the normal functioning of your life.
I’m confused. Is this over a lifetime or the most at a time during your lifetime?
Is it though? There are public health concerns with regards to sexual activity. It’s not like there are zero negative externalities with promiscuity. If people are socially distanced, masked, and otherwise being as careful as possible I’d agree. The spread of monkeypox suggests folks aren’t being responsible during a pandemic.