Cunt Toast
The crust that forms on the crotch area of a woman's underwear after she has worn it all day, usually due to the drying of normal vaginal mucous secretions.
Girl A: "I wasn't going to change my underwear before my date tonight, but when I went to the bathroom I saw it had a layer of cunt toast on it."
Girl B: "That's fucking gross don't tell me that shit."
Girl B: "That's fucking gross don't tell me that shit."