A redneck adolescent. From the movie "Deliverance", based on the novel by James Dickey. He is a blond, banjo-playing teenager who appears to be somewhat shy of the customary 46 chromosomes. He engages in a musical duel with one of the city-slicker canoe trip vacationers prior to one of their members being anally violated by someone undoubtedly related to the banjo player.
Dude, we must be lost. I think I just saw porch boy a few miles back.