The heady erotic charge of fundoshi needn't acknowledge any borders of sexual polarity. The fundoshi, in a sexual context, is one of those lucky objects that can exist anywhere along the spectrum of sexuality.
The simplicity and beauty of the human design often gets forgotten in the rush to glorify or vilify specific types of sex. Mutual bodily attraction is a fairly simple concept, but it gets corrupted with the parallel concept of reproduction far too often. Sex is fun, and when it's done right, safe and uplifting. It's also necessary! Yet it gets bogged down with moralizing of all sorts, and ends up a source of shame and judgement for too many people.
The fundoshi might be a fetish prop for one partner or the other, or both. But just because that's where it crops up the most on the internet filter (in a fetish context) doesn't mean at all that's the only way it gets used. Outside of all the titillating visuals, the fundoshi probably leads a rather humble life.
Below are some couples, often both clad in fundoshi, enjoying fundoshi together.
this enjoyable arrangement with the fundoshi has been going on a long time.
and it has certainly taken on some colorful and creative appearances.
the possibilities for couples are really endless. One could drop a robe or a gown and reveal their fundoshi to an unsuspecting partner. Or putting the fundoshi on their partner could become integrated into foreplay. It's easy to imagine feverish fingers working at those same twists of cloth moments later, the fabric dampened by anticipatory perspiration and sexual juices. It doesn't take a great leap of the imagination to feel her fingers massaging his balls through a thin film of material; or his tongue lightly tracing the edges of her fundoshi as she pushes her hips up toward his face...
Below, a young Malcolm McDowell gets acquainted with a lover's fundoshi-style garment in the movie Caligula:
This next couple seems to favor matching fundoshis, perhaps increasing their bond of love like an identifying badge:
And of course the possibilities aren't restricted to just conventional couple sexual dynamics; groupings of any imaginable combination are possible in all their multi-sexual splendor, rife with possible couplings and triplings and multiple penetrations...
(Honestly, that's a whole other direction we could go off in.)
...But there's something simple and beautiful about two beings blessed with complementary sexual equipment, the glint of love and the intoxicating buzz of passion. Under such fortunate circumstances, the introduction of an 8-foot swath of twisted fabric can be just the thing to push this heavenly scenario right through the lovely warmth of sunset-lit skin into some unknown and all-consuming ocean of unfathomable pleasure.