Someone who sucks a penis. In other words playin the flute or giving a blowjob. The term "Flute" in skin flute is reffering to someones cock, penis, weiner, pecker, helmet head, dick, disco stick, etc.
Guy 1: That guy named Jordan from the coffee shop is a proffesional skin flute player!
Guy 2: I know yesterday he tried to play my skin flute but i beat his ass.