It feels more weird than painful though if a very large sound is used I guess it could become painful. Even though I am a masochist that is not something I think I want to try for fear of damage.

What I have done on many occasions is have the Domme put some Tabasco sauce in there. That takes a while to kick in but it is definitely painful. Once the pain starts it will run its course so be warned. One interesting plus with this particular torment is some of the ladies get a big kick out of doing it. In one dungeon whenever the Domme would do this she would invite any idle Domme to watch at no extra cost. Normally when a Domme summons an audience it is for the amusement of the sub but in this case I believe she felt that she was treating her coworkers.