When your are about to go down on your fine lady friend, but first you nee to check if she has washed so you put your face only a small distance away from the vagina under scrutiny and you use your left hand to gentle waft the air towards your nose while taking a stealthy inhale to check the pungency.
Nan!? NAN!? Are you trying to gust me!? Ridiculous! You better know I wash bitch! - or - I've caught you gusting me you saggy little shit!