When you have to shit so bad that you start crapping before your cheeks actually make contact with the toilet seat. Usually involves a running start with pants down.
Dude, i payed the price for eating all those burritos last night. I just barely pulled off an emergency landing when i got home.
1) Start by standing up and 69'ing with your girl
2) Continue to eat her out
3) Right before she climaxes completley release her from your grip and watch her fall to the ground landing on her neck.
I was lickin' like mad till I had to pull off an Emergency Landing!