When two sexual partners (generally female) each go down on a guy and take a side of his penis each (left side/right side or top/bottom), going down on him in a harmonica-like fashion.
Dude, I was hanging out with Katie and Kristy last night and totally got double harmonica'd. I even made them hum the tune to the wheels on the bus.
so much fag if it exploded it'd get gay everywhere.
Arronx is such a faggomite, man – dude it just waiting to blow.