More unexpected for him than everyone else.
Every year, my 6th form college holds a charity fashion show, organised and run by students, and it's great fun. This year, I was on the organising committee, as well as modelling.
As assistant director I was asked by the supervising teacher if I thought we (the shop models) would need any supervision on the nights in our dressing rooms - mainly for the lads. I assured them we could cope, and we were left to our own devices.

Everything went swimmingly apart from one little problem we had with the boys.
Now, bear in mind it takes a certain type of 17/18 year old boy to audition as a catwalk model. A type which is usually very confident, a type who loves himself more than a little bit.
Almost all our male models were just like this. And would they keep their clothes on? No they would not.
I'm not talking just wandering round topless here, that was happening too, but believe me, not a one of us girls was going to complain about that. I'm talking running round the dressing rooms more naked than a nudist in the bath.

During the interval, we were confined to the two adjoining classrooms we were using as changing room and all the models had congregated in the lads room to watch and laugh at the three worst offenders have a wail of a time.
On was on the teachers desk, with only a helium cannister to preserve his dignity.
Another was dancing on top on a filing cabinet, hand over his bits.
And the third, who we shall call Matt, was stood in the corner, a balloon covering his man parts.

Unfortunately I can't claim the idea behind this one. It was my friend Max who leaned over, pointed at Matt and whispered "Don't you just wish you had a pin right now?" And that, dear readers, is when the metaphorical light bulb above my head sparked into action.
There was a tin of dress pins in the girl's room for last minute adjustments. Everyone was too distracted by the flashers to notice me slip out to fetch one.

Pin in hand, I sidled up to Matt. I hadn't shown much interest in him before this, so he looked at he funny and asked me if I was sure I wanted to get that close.
"Oh yes" I replied. "Definately."
And in one fluid movement, I flicked out my pin and popped his balloon, fully exposing him to the entire room and giving him one hell of a shock. The look on his face was priceless.

Best part was, it was all being filmed by another model, who, in a moment of beautiful coincidence, just happened to zoom his phone in on Matt's crotch seconds before my arm flashed across screen, capturing everything.

Length? I couldn't say, but the balloon wasn't very big.
(Applebite Uh! A cow!, Sun 31 May 2009, 19:58, Reply)