A male of Korean-descent, usually sporting a fauxhawk or comb-over haircut with excessive amounts of hair gel and dye, graphic tank tops, and tattoos with bible verses or Chinese characters, who spends most of his time lifting, playing online computer games, and hitting on females at bars that serve soju.
Sylvia: "Look at that KFB over there trying to get with Cindy. He's so muscular, though, and I like his haircut. Oo look at that tattoo on his arm - wow, he's such a douche. A cute douche, though. Maybe I should go talk to him?"
Stands for Ka-friggin Boom!! A term used in the gasoline, chemical or firesafety industries for an explosion or potential explosion that is often easily preventable.
Don't forget to check for fumes before using that saw near that tank or we'll have a KFB on our hands.