CRKFO is an abbreviation for the "Carrick Fair
One".
This saying originated in Pittsburgh, PA. It refers to the way that citizens of the Carrick community/neighborhood fight. The Carrick Fair One is actually saracastic, because
people from Carrick do not, in fact, fight fair. CRKFO usually refers to multiple
people from Carrick fighting (or jumping) one foreigner (or other Carrickter).
CRKFOs are known to get out of control, and often be comical as well.