Certainly shaping to enhance cleavage, provide lift, or make their boobs look a bit larger, as well as feeling sexier, are all reasons women wear bras.
But I think the main reason is propriety. Let's be honest: You see a chick with boobs swaying and/or nipples poking in plain view, and we guys think she's more likely to fuck, and so we're more likely to make a play for her or at least talk about her with other dudes.
I came of age in the late 60s and 70s, when lots of women shucked their bras, some to make a "women's lib" statement or indicate their sexual freedom, with others following for different reasons--comfort or because certain popular clothing styles were incompatible with bras. And then there were those women who went bra-less simply because everyone else did.
Funny story: When I was in college, I was working on this psychological research project with a couple of professors and several other students. Working in teams of two, our job was to go out into area high schools to administer assertiveness assessments to juniors and seniors, then come back and assign scores to their recorded responses. Melanie was on the project, too, and was an extra fine-looking co-ed with a stunning pair of big boobs, never encumbered by a bra. I wasted no time in pairing up with her.
Partners spent a great deal of time together, so I got to know Melanie quite well. Like me, she enjoyed herb and laughed a lot, and was extremely sexy. We made what could have been a very boring and serious project enjoyable, as we always had a lot of fun together.
Ever meet someone and know right away you're going to fuck? That was Melanie and I.
We'd both just broken up with long-term lovers, and neither of us wanted to jump back into a committed relationship, but we were surely horny for one another. We worked together on the project at least twice a week, so, whenever we were alone, we had sex. Since we were alone a lot, we had sex a lot. In fact, we'd volunteer to drive out to the most far-flung county schools just because it would take us into the backwoods where we could park on some lonely back road or get out and screw like rabbits in the woods. You know, fuck on the way there, then again on the way back, maybe again when we returned.
Though it was the very early 80s by then, Melanie was a throwback to a somewhat earlier area—a hippie-chick type who liked to smoke herb and share her bodily goodies, which were exceeded in their goodness only by her facility in using them. She was just so free and easy and relaxed about screwing. Never has the expression, "casual sex" applied more than it did to our relationship.
With very dark eyes and straight brown hair hanging alongside a slim, smooth neck to a couple inches below her shoulders, Melanie was forever smiling, her bright teeth surrounded by a wide, full-lipped mouth that veritably screamed "blow-job." She had no clue about her ethnicity, but her somewhat short stature; dark, flawless skin; and sharp, well-defined features suggested a Mediterranean heritage. That would also account for her dark brown nipples--always erect--and equally dark, dangling pussy lips.
Not skin-and-bones, she was nevertheless quite slender, with a terrific pair of fleshy little buns that bounced alluringly with each step beneath the loose, nearly threadbare seat of her faded Levi's—the only kind of pants she ever wore. At the terminus of her slim limbs were small hands and feet, punctuated with extraordinarily long fingers and toes. Not only was Melanie ambidextrous, but also she was equally adept with both feet: She could do practically anything with them, even write with either one in beautiful cursive script!
It would be difficult to select the best of her goodies, as they were all so tasty, but if I had to, it would be her boobs. It was not immensity—only a tad bigger than baseballs—but their shape, make-up, and how they were situated on her body that made them truly outstanding.
They came out from her chest, hung down to form a crease, then swooped back up and out to the aforementioned perma-rigid nipples, surrounded by ultra-smooth, almost-as-dark areolas a good two inches in diameter, giving the tits a sort-of upturned appearance. Her small upper torso and impossibly skinny waist—Melanie weighed only about 105 pounds—coupled with what were honestly just medium-size tits emerging from high on her rib cage, made them appear larger. Rather than splaying outward, they hung very close together, creating deep, natural cleavage that begged, "titty-fuck me!" Pendulous but not at all saggy, her firm, dense bazooms would sway and bobble even when she moved ever so slightly.
She never let on that she noticed practically every guy and more than a few gals, stare at them, though I'm sure she did. That's one of the things I liked about her, not hung up on her looks, though she could have easily been.
Leading the research project were two psychologists, a married couple. She was the one clearly in charge. They approached me, saying they'd had a few complaints from the schools about Melanie, and could I please say something to her, as she was doing an otherwise fine job, and they definitely wanted to keep her on the project.
I asked why they didn't speak directly with Melanie, and they said it was a delicate issue, so--knowing she and I were friends--felt it would be more comfortable for her if I was the one who said something.
I didn't like the smell of this, but I asked what they wanted me to do. Well, they said she had become something of a distraction--specifically her breasts--to the high school boys, and would I please ask her to start wearing a bra? I'm sure they had no clue that Melanie and I had become fuck buddies, and that I was intimately familiar with her ta-tas.
Frankly, in terms of support, she didn't "need" a bra, as her boobs were far from huge, and quite dense and firm. Further, this was in an era in which lots of women went bra-less, so it was not at all out of the norm. Thus, I was a bit galled that they'd foisted this chore onto me, but the way they put it to me, I really wasn't given a choice.
Of course, that these Ph.D. assertiveness experts were too passive to tell her themselves was painfully ironic. And that one was a woman who herself went bra-less was even more ironic! Of course, though she was quite attractive, she had fried-egg tits with tiny pink pointers only visible if you positioned yourself strategically for a downblouse, like I of course did. I can't say for sure, but her real motive may have been jealousy over Melanie's much nicer breasts.
So I used the appropriate assertiveness technique to communicate the news to Melanie myself. Timing is everything, so, with her on top of me in a 69, I told her while simultaneously eating her pussy and titty-fucking her. Far from offended, she got a big charge out of it and cracked up laughing.
"I don't even own a bra!" she chuckled. "My boobs started popping up when I was 11, and I was out of a training bra in a few months and soon into women's bras. I tried every kind made and found all of them constricting and very uncomfortable. By the time I was 14, my boobs were done growing, and Mom said it was OK to ditch bras. She found them tortuous, too, and hadn't worn one since the mid-60s. Our tits are still almost identical, and hers have held up just fine over 15 years of freedom, so we don't need a fucking brassiere. The last thing I'm gonna do is buy and wear a bra!"
It was hard to argue with that, and I suddenly had the urge to meet her mother! And it was impossible for me to be pro-bra, for I loved Melanie's boobs--always there for viewing and squeezing pleasure. Yet, we had a problem that somehow had to be solved.
So, we went through her clothes, she trying on first one top then another, and finally found a long-sleeve shirt constructed of chambray--a light weight denim fabric. It did the best job of hiding her perma-pokies, but they could still be seen, even with a tee underneath. Of course, both shirts did little to restrain the jiggling and swaying aspect of her boobs. Even so, it was a big "improvement."
Though small of frame, Melanie had a projecting, Bo Derek-like rib cage over a narrow waist that simply put her perfect, large C-/small D-cup tits on display. Personally, I think even had she worn a bra, they would have still been ubiquitous. You just cannot hide boobs like that on a girl like her no matter what you do.
So, she started wearing the chambray shirt with the tee underneath when we went into the schools, and we wound up the pre-assessment phase of the project in spring. If there were any more complaints, we never heard about them.
We'd both just finished the spring academic quarter but stayed in town because we had jobs, and the leases on our apartments wouldn't expire until the end of Summer, anyway. I'd stopped by her place late one morning for a few bongs and boinks, and we were sitting there naked on her bed about to fuck when the phone kept ringing and ringing and ringing.
These were in the days before answering machines, and Melanie thought it might be work, so she finally picked it up. It was the male prof, who said he desperately needed someone to go out to a school in the boonies to do assessments on several kids who'd been absent when she and I had been there before. The sample size would be too small for meaningful statistical analysis if a few more subjects weren't added.
He said it was the last day of county school exams, and the superintendent had agreed to hold the students over that day only, so she'd need to go immediately to get there in time. She was him-hawing, but the prof said he had grant money left over, and it was worth $500. She was still trying to get off the hook because she had a job waiting tables evenings--as did I--but I had nothing else to do that day and agreed to go with her. That would cut our time in half and get us back to town in time for work and still put $250 in each of our pockets.
We'd done a bunch of bong-hits and were horny as devils, but there was no time even for a quickie so we hurriedly threw our clothes on. In such a rush, we forgot all about the chambray shirt cover-up, so she just wore her usual faded hip-huggers jeans and a thin tee-shirt, bra-less, of course. Off we raced in my convertible to the school way the hell up in the mountains.
With the Talking Heads blaring on the drive there, she blew my raging hard cock as I had one hand on the steering wheel and the other fingering her dark, lippy pussy. But the damn road was so narrow and treacherous that we were both too tense to cum.
When we arrived, the principal was the only adult left, and, obviously in a hurry to get out of there, cut short our usual polite spiel and escorted us to the room where we'd do the assessments. I was looking out the front window and saw him drive off with a foxy middle-aged woman waiting in his red Ford F-350 duelie truck. As soon as he got in, she slid over to his side of the cab and gave him a nibble on the ear. I knew from being there before that they were married, but not to each other. She was the school librarian.