New Jersey Curtsey
Dirt, marks/stains, redness of skin (if in a skirt, dress, or shorts), or general debris on a girl's knees or clothes indicating that she has just performed oral sex. Most often this occur outdoors or in some other relatively public venue, since this is where stain-causing elements are most often present (think movie theater or public restroom floors).
When Jane and her boyfriend came back inside, she had a total New Jersey Curtsey. Those jeans must be ruined from all the mud on her knees.