It is not natural for a person to be writhing around so much and tugging at their britches. You know, I would not be surprised if the photographer put the powder in there himself. I know that it can be hard to get a model to hit the poses that you want them to, but resorting to sadistic methods like this is simply too far. Who did this guy think he was, Kubrick? You cannot just go around throwing itching powder on everyone you choose to, that was banned at the Geneva convention. Besides, once you break that seal and use those tactics you are opening up a gateway to all sorts of other more nefarious activities.