Any of several ancient styles of garment designed to cover the genitals. Usually made from a folded and tied length of cloth, sometimes held in place by a belt. If it has a dangling length of cloth hanging in front and/or or behind, that part is called, for Danbooru's purposes, a pelvic curtain.
Fundoshi are a range of specifically Japanese styles of loincloth. The loincloth's modern replacements are panties, briefs, and boxers.
The following tags are aliased to this tag: loin_cloth (learn more).