CBK
Shorter version of the term Cockblock. Its used to confuse females who figure out the art of cockblocking. 

Also used as a "gang" for known cockblockers.
Your friend moves in on your woman, he's CBKing you. 

Your friend is hitting on a girl, you walk up with your cellphone and say Hey! Your girlfriend just called me. He replies "STFU COCKBLOCKER"