Hold it in

You decide to hold it in. You know you have a somewhat small bladder, but it can't be that small. You'll hold out until the end of the demonstration.

...Unfortunately, your name stll doesn't get called after 30 minutes later and you can feel the urge getting stronger and stronger. If you had known it'll be like this, you would've gone to the bathroom earlier.

"Uuu..." you mumble to yourself. You can feel that you're approaching your limit.

The worst thing that can happen if you let it out right when you're in front of everyone. You will never be able to live the embarrassment if that happens.

Suddenly, you get an idea. What if you relieve yourself a little bit here? Just to reduce the pressure? Everyone's eyes are on the demonstration so no one should notice if you let out a drop or two. And the color of your leather shorts are dark brown so the wetness shouldn't be noticeable.