It was particularly obvious to everyone when the couple had been, shall we say, rather "inexperienced" up until that point in their respective young lives.
Literally overnight you'd see the change in how they interacted.
There were longer stares into each other's eyes, as if they were now more "serious". After all, that's what intimacy does to people.
But also, it was as if the guy just couldn't keep his hands off the girl's stuff, huh? Remember that?
I mean, there was just no denying it. The two of them were now "going all the way" together.
Well, want to know something? Years later, even though we've all (hopefully) grown up, nothing has really changed.
You really can tell when a couple is having sex, even if they've tried to engineer things so that the signs are as subtle as they can possibly make them.
But hey, even so...the truth is that everyone else's "radar" has become more sophisticated at picking up those signals that a couple is having sex.
Add it all up and there's really still no hiding it.
The signs are predictable and tend to cross sociological, ethnic and even international boundaries. That is to say, there's a pattern that can be observed.
Even though I'm going to spell out five key components of that pattern today, I have a hunch that you already know what it looks like when you see it.
For example, we know a guy who's a married business owner, but has a penchant for hiring pretty women.
That alone is going to raise suspicion among others as to what his intentions are. But sure enough, he tends to exhibit all five of the indicators I'm about to list whenever he's hanging out with certain employees.
I've always found it amazing that this guy could possibly think nobody is intuitive enough to figure out what's going on.
But weirdly, it's actually not unusual for guys in particular to get pretty cocky about showing subtle sexual indicators in public, thinking people around are socially oblivious.
They're not...hence one very good reason why I'm writing this as a public service to you also in case someday you're that guy.
The rumors will start if people see any of the following five dynamics going on, and they'll likely have merit.
1) Protective Instinct
Sure, a good man is always seeking to be a source of safety to women around him, regardless of his relationship to them.
But when a guy starts having sex with a woman, he naturally becomes extra protective of her...physically, emotionally and yes, sexually.
Have you ever socialized with a guy who's in the company of a pretty woman he swears is a platonic friend, but becomes a little too edgy when someone else banters with her, flirts with her or even bumps into her? Bingo.
2) He Touches Her Just A Bit Too Often
Like in high school, a guy with a new and exciting sexual partner tends not to be able to keep his hands off the merchandise.
Granted, if he's got any social awareness at all he's not going to walk beside her with his hand in her back pocket or hang all over her giving her hickeys.
But make no mistake, physical touch is unavoidable, probably for both of them. They just can't keep their paws off of each other.
If you see touching going on when it was unnecessary, treat that as a valid sign that they're getting frisky together.
Also possibly look for him to nervously parry her touchie-feelies if she's the one lacking restraint.
3) Physical Closeness
For example, the presumed couple might seat themselves in a group so that the body positioning relative to one another is unmistakably sexual.
He might pull up a chair behind hers and rest his hands on the sides of her chair with her chair between his legs. Yes, that sounds pretty obvious, but you'd be surprised. Again, these guys think they're doing something innocuous.
4) Inside Signals
The two of them will often have little secret non-verbal signs they'll send each other when in public situations. Oddly enough, that's really something that tends to come with physical intimacy.
Others around them may not understand the signals, but they see them and get a firm grasp of what's going on at the "big picture" level.
Interestingly, you're more likely than not to see these signals at big social events because the couple will likely go out of their way not to be joined at the hip the whole time, lest rumors start.
Splitting up while socializing also limits the possibility in their mind of people potentially asking about the nature of their relationship.
5) Being Seen Together At Odd Times
A major clue that things have gotten sexual between two people is when you see them together when or where they don't have to be, nor should they be.
For example, you stumble into the neighborhood convenience store at 11pm and you see them there. They'll probably act all casual and cordial, especially if they're good at camouflaging things, but don't be surprised if they freak out and swear you to secrecy instead.
After all, depending on the exact circumstances this could be tantamount to being caught red-handed.
Obviously, the utility of this article lies not simply in being able to recognize what's going on in other's lives, but more importantly to help you be aware of how others may be able to read your sex life like an open book.
For the record, I really do believe you can't completely eliminate all the signs I've outlined above.
But knowledge is power.
Knowing what they look like helps you stay aware of yourself and limit your social exposure.
It's also important to note that you really can't draw conclusions based on evidence that matches up with just one of the bullet points above.
Rather, it's when you see a pattern that fits several of the items on the list that you can begin to size up the situation more accurately.
What did I miss? Leave it in the comments.