butthole sweats

Where you are in a public place (like school or a museum) and you have a mad batch of diarrhea brewing... its so bad that you're clenching your anus so as not to leak out any butt sludge before you safely arrive at a toilet... in the meantime, you have a stream of sweat running down your back, and down your butt crack...

I ate some bad meatloaf at lunch today, and later I got a terrible case of the butthole sweats while in english class... I thought my colon was going to explode all over my chair!