What does backseat surprise mean?

backseat surprise meaning in Urban Dictionary

When you are making love in the rear of your car and she loses control and shits on your own car seat. Each morning you appear at your back chair and there's a brown shock awaiting.This really features happened certainly to me 2 times, as soon as in my own moms and dads automobile and my dad found it and when in my own car.My old man could not workout where in fact the poo emerged from..