Reverse day 

Reverse day is a day of the week that occurs every Monday and which is called “Reverse Monday” and was confirmed on March 28 2006

Today it is reverse day

Reverse day by Thenameisjeff17530 January 28, 2019

national reverse cowgirl day 

June 21st, the day in which you have sex using the splendid and pleasing reverse cowgirl position

hey it’s national reverse cowgirl day! you know what that means

national reverse cowgirl day by The Real OG 13 June 15, 2018

National UNO reverse card day 

On October 21, any time someone says they will do something to you, you can say "but it's National UNO reverse card day" and they must either do it to themselves or claim "but it's National UNO reverse card day" back. In the scenario the last person to say "but it's National UNO reverse card day" before the end of October 21 is the one to receive the action in the end.

Wizard: I'm gonna punch your face!
Bard: But it's National UNO reverse card day.
Wizard: Dies of 1d4 punched self in face damage.

National UNO reverse card day by EchoTheMythical October 21, 2021

National Reverse Cowgirl Day 

November 22nd is the one day only that women must do reverse cowgirl

National Reverse Cowgirl Day

National Reverse Cowgirl Day by bigboppo November 22, 2020

Reverse Halloween Day

On October 13th, instead of recieving candy, you take it from others. You also dont wear a costume.

I celebrated Reverse Halloween Day by steal my bosses candy.

Reverse Halloween Day by The fat kid next door February 18, 2009

Reverse Patrick's Day 

its like the patrick day but if you have green color you will get pinched, it happens on September 17

It is Reverse Patrick's Day

Reverse Patrick's Day by random_redditor69 September 4, 2021

Macy's Day Parade Reverse Bidet Soufflé 

The delicately balanced art of getting a good ole fashioned mouthy while the female is taking a dump (a reverse blumpkin) while using a bidet to clean her bhole.

They japanese local was pleased to hand out many macy's day parade reverse bidet soufflés for the simple price of some eggs tyrone.

Macy's Day Parade Reverse Bidet Soufflé by @Ericfordays September 3, 2012