Here are a few of my favorite boy pics.
As far as the loincloth in Last Temptation.
I suspect the loincloth was prepped before the scene was shot.
It would have come off with a firm tug.
It is easy to get a loincloth to rip off.
All you need is a relative flimsy fabric and a few strategically placed scissor cuts and it will tear right off.
I have done this many times with bottoms wearing briefs.
Cut the elastic on each side and on the leg bands and they tear off with one good tug.
Better do prep the briefs before the bottom puts them on so they are ready to go
Works with t-shirts also.