P.E tent
When a guy gets a hard-on in his underwear in the boys' changing room during P. E. and gets caught red-handed.
My buddy got caught with his pants down and a boner in the P. E. tent. Classic.
I saw my teacher walk in on a guy with a full-blown erection. He looked like a deer in headlights.
The P. E. tent was the scene of the crime. A guy was caught with his pants around his ankles.