Shirting your pants is a metaphor for shoveling worn sweaty rags into a shirt and then marinating it in blood and pee. You take the 'shirted' item, place it in some pants, preferably an expensive pair by the Shirtee, and nail it to their doorstep. Shirt on fire is, as you can guess, a variant where the Shirter sets the Shirtee's Shirted pants on fire.
"Yo man, I just shirted my mum's pants!" "Haha! Oh, Jerry, you're a psychopath." "Watch out, man, I'll shirt your pants too..."
by MorrowMorrow November 10, 2021