Sometimes teenagers invest in a few pairs of black underwear because their rhythm and amount of flow can be unpredictable, and sometimes they don’t quite change the tampon/pad in time, causing their underwear to become stained. Black underwear doesn’t show stains as much as other colors, so you can wash them and have perfectly fine underwear again.
Most often, though, it means close to nothing, though men find it sexy and alluring.

It also depends on the girl’s age and her knowledge of the big, wide world.
It’s widely accepted that clothing can convey a message (which may not be intended). For example, formal dress conveys the message that one is at, or is going to or from a formal function (unless one is simply trying on the clothes). That is one reason why failure to wear appropriate dress can cause problems and be interpreted as a lack of respect.

It’s also known that teenage girls sometimes dress extremely sexily just because they think it’s fashionable and are completely unaware of the misleading messages they convey. This would apply more to outer clothing than to underwear.

More input and opinions:

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From what I have experienced, women find black underwear sexy, and they know men like it too. Also, but this is not always the case, from my experience, when a woman wears black underwear, they planned that ahead, which means they wanted you to see it, whether it be a bra or panties, they intended for you to see it, whether that means before intercourse, or just whenever. I think it’s safe to say if a woman is wearing sexy underwear, and she is showing it to you, she already planned this out. I’m not saying if a woman has on black underwear it means you’re going to get laid, but it’s not too far fetched to think that that is a possibility. Mind you this is all from personal experience.

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WAIT!! …I think the real question is: how do you know she’s wearing black underwear?

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it just means she felt like wearing black underwear that day. it’s nice to have a variety. But…

We live in a world where clothing often has a symbolic significance and gives off messages and the question is surely about the meaning or symbolism of black lingerie. 🙂

Hold Up:
First off I am twelve and I own black underwear to have black underwear. I don’t think I plan on having sex thank you very much but I just have some so… I am not just gonna throw them out. I find them annoying because you can see them through a lot of things so I don’t wear it a lot anyways but when I do… I don’t wanna get laid so that is just nonsense.

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As we can see, black underwear means different things to different people. If you want to know about the black underwear, ask. I would say that the cut of the underwear, the fabric it is made from and if she is wearing a matching bra say more than the color. I own some very fancy black underwear and I own some really old, comfy cotton black underwear. I wear black underwear if I am wearing black pants or a black dress but I also wear black underwear when I plan to be seen in it. So, I am guessing that the situation, the kind of underwear and the attitude of the girl wearing them will tell you everything you need to know about why that particular girl is wearing that particular pair at that specific time.

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OK if you ever saw the movie the 10 things i hate about you it explains it as if you have black undies than that means you want to have it some day but i think it is; is that you just chose a bunch of underwear and bought it in other words it doesn’t mean anything

WAIT ONE SEC….
Americans say that some MATURE girls wear it (and show it just a Little) as a hint that they either ‘want it’ or ‘gonna get it’. but otherwise maybe the girl you’re talking about JUST FELT LIKE IT, i just ‘feel like it all the time!

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I don’t really know how someone would know you’re wearing black underwear, unless it shows under see-through clothing. Yeah, like people have been saying, it is better to wear black underwear when on a period. But other than this, it shouldn’t really matter! It doesn’t mean anything!