Tha JC is a dance where you are pretending to get fucked in the mouth and in the butt at the same time. Doin tha JC is when you take both of your hands and hold them as if you were holding a rather fat penis.( One fat penis in each hand) Then you take one of your hands and thrust it towards your wide open mouth but dont actually hit your mouth with it. When your hand reaches your mouth you must make this noise very loudly "GACK GACK GACK GACK!. Then you take your other hand and thrust it at your ass, but you must actually hit your butt with your hand so that it makes some noise. Get these steps in order and you will have it,
"Dude, this guy in line ordered some green tea today at the restaurant. So I started Doin tha JC on his gay ass."