Top definition
When you are having sex in the back of your car and she loses control and shits on your car seat. In the morning you look at your rear seat and there is a brown surprise awaiting.

This actually has happened to me 2 times, once in my parents car and my Father found it and once in my own car.
My old man could not work out where the poo came from..
Last night i was fucking sally in the back of the car and when I looked at the rear car seat i noticed that she left me a backseat surprise.

Or Whats that brown stuff on the rear seat? I am not lending you my car ever again!

There's poo on the car seat, honey can you check the kids shoes?
by Woody woodPecker August 10, 2012
Get the mug
Get a backseat surprise mug for your boyfriend Georges.