canadian border patrol 

When doing it doggystyle, take your partner over to the window so he/she is facing out. Take a break for a few moments, and covertly invite a friend to take your place. While he continues, she assumes it is still you behind her, so then walk outside the same window and wave to her as if you were simply passing by.

Me and Kevin pulled a canadian border patrol on her, she didn't know what happened and she went nuts.
I'm gonna visit her in the asylum in a few days.

canadian border patrol by Dan Curtsinger August 15, 2006

Canadian Border Patrol 

This hilariously tragic sex prank is achieved through the following: You begin normally having sex, you then tell her to get on all fours (Doggystyle), all the while covertly aiming her towards a window, immediately after, your friend will come and switch places with you. Then, you will calmly walk past the window, then turn and wave at your misguided partner.

Dude: OMG MAN, MEMBER THAT BITCH JULY?
Guy: Yeah...?
Dude: Me and Man totally pulled a Canadian Border Patrol on her.
Guy: Dude... you're fucked up... In a funny kinda way!
*High five*

Canadian Border Patrol by Cpt. Dan May 5, 2008