[The following has been patched together from some emails sent to me by the author. Carceri]
I had an experience in my younger days with a wire device which these boys I used to hang around with called a Cheeswire. It was a wire attached to a rail and the other end had a wooden toggle. They would pull it through between the girls legs and using the toggle pull it up high so the wire dug in between the lips. Very persuasive!
When I was in my teens I used to hang around with a group and i'm not sure how but the interest gradually drifted to what we now know as SM where the boys would dare the girls to undergo dares to see how much discomfort they could take.
It started with silly things like pushing a rolled up peice of sellotape against a girls pubes and then pulling it away to se how much pubic hair they could pull out and have stuck to the sellotape. Then they would hang clips and weights onto the nipples and then the lips of the fanny and then one day we were all out walking along a quiet lane and one of the boys pointed to a metal fence. It was one of those with narrow metal bars and he dared a girl to remove her knickers and sit astride the bar. As you can imagin it was very uncomfortable but they dared the girl to keep her feet off the lower bars so all her weight was on her fanny. They boys got so excited and then dared each girl to see who could sit on the bar the longest. (A pony I guess)
Then one day we were in a storeroom and there was a length of wire hanging down from the wall (I think used for cutting plastic or cartons) so one girl was asked to stand against the wall while a boy pulled it between her legs, another guided it between the lips of her fanny and then it was pulled up tight. Again we all had a turn at straddling the wire and I can say it was very painful.
I guess they were a pretty wild bunch that I hung around with although I thought it quite normal at the time. It seemed to be quite the thing for groups of kids to dare each other. I knew some others at the time who would dare girls in their group to "streak". They would quickly remove their clothes and quickly dash along a street or through a park. I guess ours was a little different as pain was involved.