Look guys, I think you are all being way too cynical.
There may be fragrances that cause a particular woman to perhaps shake uncontrollably so much so that her panties shake loose and fall down. This is of course no guarantee that she wants to have sex with you (maybe a little nauseous), but if it does happen, you should warn her, because if she tries to walk, she may trip over her panties and fall over and hurt herself.
Panty droppers are dangerous, dudes!