The Day of Ass-Slapping 

It is a legendary way, where all humans gather to celebrate slapping of ass. On November 13th, a Friday, each human being is to slap the ass of at least one person.

Mac: "Yo! It's The Day of Ass-Slapping!"
Dead: "Really?!"
Mac: "Hell yeah, c'mere boy."

The Day of Ass-Slapping by Dr_Machintosh November 5, 2020

International ass slapping day

On April the 6th every year you are supposed to slap a a girls ass to celebrate the holiday

Daam that ass nice by the way it’s international ass slapping day so you know what I need to do.

International ass slapping day by Yoboycam May 22, 2018

Slapping ass month 

In October people are allowed to go around slapping people’s ass’s and not get in trouble so girls/guys can slap each others ass’s

“Omg Jake Tyler just slapped my ass” - Anna
“Welp it’s October which means it’s slapping ass month”- Jake

Slapping ass month by Gothgirlcliche October 6, 2020

slapping ass

When you thrust so hard during sex you make a slap sound

Man we were SLAPPING ASS so hard last night she almost fell off the bed.

slapping ass by Bobsheretofuckyobitch June 7, 2018

slapping the ass 

A movement of the hand that results in smacking that ass forcefully. This is also qualified as a turn on for some fifty shades of grey fans.

She was slapping the ass.

slapping the ass by Everybodywaskungfufighting November 11, 2015

ass-slappin' 

adj. exciting, great, excellent.

"Come to my party, it'll be an ass-slappin' good time," said Mandy.

ass-slappin' by Joe Nobody January 20, 2004

Ass snapping

Placing a hand (or thumb, index, and middle finger) inside an anus to preform a snapping motion for immense sexual pleasure.

"I came so hard when he started ass snapping me last night"

Ass snapping by milkyfire April 30, 2019