Littreachourousbackstabber is short for Literal Treachorous Backstabber, it means someone who betrays (or figuratively "stabs you in the back") by literally stabbing you in the back.
"My old friend Carl stabbed me in the back yesterday, literally"
"What, so he's a littreachorousbackstabber"
"What, so he's a littreachorousbackstabber"
by Ya Friend March 25, 2022