What is Lick my ass crack?

i did and no one will stop me

person 1: hey bro how are you doing
person 2: i licked my own ass crack
person 1: how bro i wanna try

Lick my ass crack - video

when someone annoys you and you get triggered but don't want to swear

person 1: NUUUUUUUUUUU I LOST IN ROBLOX
person 2: guess who killed you
person 1: lick my ass crack