When a femboy prolapses his asshole, and the loosening of the ass causes absurd amounts of cum and shit to shoot out of the aforementioned asshole at Mach 10 but in such a way it boomerangs back into the asshole with this process repeating until either death or the asshole goes back inside
by AsianLongMan April 3, 2025

It's literally just nothing
by Gwortley1 June 8, 2017

When two people are having sex, someone runs in completely naked except for a mask (preferably some sort of animal mask) slaps whoever is on top on the ass, screaming and jumping and laughing the whole time, then runs out of the room and closes the door.
Dude, Bry was with his girl last night and I gave him an ANIMAL SURPRISE...I knew that gorilla mask would come in handy. He showed me the red mark on his ass...NICE!
by Grindhouse February 19, 2011

The act of sneaking up on a person and shoving your arm up there anus till you can control there mouth like a ventriloquist dummy
by Rexstfs December 23, 2021

A fleshdog surprise is what happens when you do a handstand with your homie and shit while pointing your asscrack parallel with the floor and then have your friend lay the turd between your cheeks like a hotdog wiener between the buns then piss on it. Serve Warm
by freese daddy August 4, 2020

The resonating sound a kindle makes as it bounces off your skull when you fall asleep while reading.
by Web4less July 18, 2021

Ass-hole surprise, the act of quickly and without warning, ramming your penis and or dildo into an unsuspecting females anus.
by Christianusaf July 23, 2016
