Oh god, I pulled something like that the first time I got wood around a girl. We were cuddling and watching a movie at the theatre, and she had her hand in my pocket and was attempting to touch the goods, and I was like 'BRAGLEforgetME I NEED TO GO DO STUFF IN A DIFFERENT THEATER' I ended up going to a competely different theatre/show room and left her there.
That relationship lasted about 35 minutes, lol.
lmfao. I bet i'll do something similar.
At our school dances, they have supervisors to look out for grinders, but people still get away with it anyway. 
I remember seeing two people grinding, and the girl was shaking her ass so loving fast, I'm surprised the boy's pants didn't set on fire.
At my school, the dance is in the middle of the gym. Teachers stand atop the bleachers, surrounding the court. Said teachers possess laser pointers, which they use to mark you, chase you down, and give you 2 detentions.