A sort of religious crazy. Commonly found in Texas, and a major faction of the Republican Party. A jmfcst will, oddly enough, be strongly attracted to black girls, regardless of age, figure, or personality.
Example 1: "Hey, look at the jmfcst over there, preaching on the corner!"
Example 2: "Damn, I hope no black girls show up. That jmfcst may go wild."