Brown knife

Brown knife is used commonly in prison after raping someone and shoving a knife up there ass

Prisoner 1: that’s the guy who snitched on vinny lets give him a little talk
Prisoner 2: hey p1 hows it goi-
Prisoner 2: AHHH STOP FUCKING MY ASS
Prisoner 1: I’m going to give you a brown knife

Prisoner 1: *Shoves knife up ass*
Prisoner 2: *dies*