It may have evolved as a male ornament, but the wrapped loincloth has many female adherents -- not only in present day Japan, but across the world and across time. The perizoma, certain bikinis, and pendre shorts are just a couple examples.
The basic utility of a fundoshi or a fundoshi-style wrap allows anyone with human anatomy to wear it. Though arguably a little more flattering over the otherwise challenging visual geometry of the male apparatus, ladies from Africa to Polynesia to Central America have experimented with the basic form of the loincloth, if not worn it daily like you or I might daily wear socks.
Speaking of fundoshi in contemporary times, it's role seems rarely to be apparel-of-choice; rather some variation of function catering to the male gaze. As a "male" garment on a female form, it plays with our expectations in the same way that a woman wearing a man's dress shirt might, and in doing so heightens the erotic tension.
There is, of course, classic-style sexy photography featuring fundoshi, where it assumes the role lingerie or swimwear might in our own culture. Whether this lends it a more classy, historically-inspired look or a cheesecake/softcore bent depends on both model and photographer, and we can find enjoyment in these photographs proportionate to our own preferences:
These are certainly not without their own innate "peek-a-boo" qualities, but they also possess a certain softness and classicism that offsets their eroticism. In most cases they could hold their ground as underwear advertisements or highbrow erotica, and the staging of the scene is often carefully done to carry across these elements, and immerse the viewer into a carefully constructed narrative.
Another way women are portrayed in fundoshi is in the burgeoning cosplay subculture. Here, devotees elaborately costume themselves as characters from anime, manga, or video games. There are large conventions solely for cosplayers, and if fundoshi is within the character's expected attire -- and fundoshi turn up more often than you might expect (especially as "fanservice") -- then no costume is complete without it:
There is some crossover here with the first style I wrote about, as many of the manga that the cosplayers are emulating either take place in a historical time period, or utilize the fundoshi in its fetish-interest role by giving glimpses up skirts or into dressing rooms where we find out that the female character wears fundoshi -- thus upping the kink factor of the storyline, if only just a little (the stories may never actually result in nudity or sex; these glimpses of fundoshi are frequently the apex of the sensual content).
From there, fundoshi are also a frequently-found attribute of less composed Asian-inspired erotica and porn, as apparently a woman in a fundoshi is highly arousing (a perspective I can certainly share, given my own preference for wearing fundoshi and viewing others in fundoshi):
This type involves less-refined camera work, self-pics, or ad hoc environments where the careful construction of an alternate reality is not nearly as important as the unvarnished call to our baser instincts. A favorite for appreciators of this more frankly erotic style is the on-all-fours shot, if nothing else a tacit acknowledgement that a nice ass in a fundoshi looks good to just about anyone! Here again, we find a number of (less emphatic) references to the fundoshi's pre-sexual, Shinto-infused history, for surely it's utilitarian uses predate its fetishization? But it's very ritual nature and attributions of purity also open it up for dirtier scenarios, where it can be utilized in raunchier ways or as a bondage prop:
These of course fall squarely into the "porn" category (though many still retain that classicist historical note), where the fundoshi is another prop, often quickly cast aside for more explicit acts, but the wearing/putting on/taking off of the fundoshi is included as a lagniappe for the fetish-inclined viewer. While this often garners my interest in viewing a piece of erotic filmmaking, the often hasty discarding of the fundoshi inevitably disappoints me.
Finally, as alluded to in the paragraph about cosplay, fundoshi certainly maintain a presence in the animation and cartooning fields, where they are either portrayed in a hypersexualized manner or as an indicator of slight inncocence (perhaps due to their "old-fashioned" connotation):
No disrespect intended against the often amazingly talented artists, but partially due to the big-eyed stylistic constraints of the manga style and partly due to audiences' taste for gravity-defying breasts and heavy-handed scenarios, depictions of fundoshi'd females often serve to infantilize the fundoshi -- rather than bring about any chance of realizing such fundoshi-augmented encounters for those of us who might be pleasantly suprised (read: mind blown) by a rendezvous that involved unexpected fundoshi-wearing by our partners.
This is not dissimilar to the kinds of associations people make with loincloths in general due to exposure to retrograde pop-culture representations like Tarzan, frontier pulp romance novels, and culturally exploitive Westerns -- despite the noble histories of the cultures who actually wore the loincloths!
There is no doubt that the fundoshi carries a heady erotic charge when worn by women, especially in its home country of Japan, where boundless videos exist of fundoshi-wrapped women wrestling, engaging in S&M, or just plain being fucked. This certainly seems to represent a narrowing of the field for women interested in fundoshi -- it's unfortunate that sex is so implicit in the garment as worn by women that simple enjoyment of it for its elegance, utility and comfort is a matter of blushing at best, suspicions of deviance at worst.
This state of affairs is somewhat mitigated by the recent emergence of "pendre shorts" (etchū fundoshi specifically marketed to women) as an alternative to western-style underwear. I can attest that etchu fundoshi are perhaps the most effortlessly comfortable underwear ever devised, so it's not unusual at all that men and women both would find out about their superiority, or that marketers would take advantage of this "new" demographic.
"Superiority" is not a word I toss around lightly, but in this case I feel I can safely say that there's not a soul on this planet that wouldn't find etchū fundoshi exquisitely comfy. Among their many advantages is that the tie that goes around your waist allows the "apron" portion to be made of silkier fabrics that wouldn't be "grippy" enough for rokushaku fundoshi -- increasing their luxury to intoxicating levels. The apron portion is also the perfect canvas for personality, whether that be expressed by traditional prints or something whimsical like Hello Kitty.
Underwear has always been a sort of secret billboard for the soul, and pendre shorts/etchū fundoshi allow limitless expression to occur within the private world of your blue jeans or your business skirt.
While this is a positive development, I'd like women who relish the thought of wearing rokushaku fundoshi without all this erotic baggage to feel like they can do so fearlessly -- fiercely. Pendre shorts are certainly a step in that direction, as far as normalizing fundoshi-wearing goes. And don't get me wrong, I'm not trying to say "erotic baggage" is a bad thing -- I find the vast majority of the depictions in this article to be turn-ons. But to truly make fundoshi a thing enjoyed by all, we need to create a comfortable middle ground where neophytes can experiment with the garment and find out on their own what it means to them. Once they've tried it out, they can take it from there...