Any given Friday when people choose to run around slapping anyone and everyone's asses. Usually, a male slaps a female's ass, and it's automaticallyconsidered okay for no reason other than the boy has proclaimed it "Slapass Friday."
Slap Ass Month is a holiday that takes place all throughout the month of October where you get to slap anyone's ass if you are there friend, cousin,co-worker,etc. And it's not gay