Similar to Best Friends Forever (
BFF), Best Enemies Forever (BEF) means two
people who love to hate each other and rip on each other every chance they get. They are sworn enemies who form a
bond of hatred so strong that it's more like a perverse kind of friendship.
Bill: "Goddammit, I hate that
asshole Craig! Who does he think he's trying to impress??"
Dan: "Dude, will you stop
talking about Craig? When did you two become BEF?"