For a girl to let out a vaginal flatulent or "quiff" into someone's mouth while they are asleep or unaware;

also known as a "Spicy Michael" when a guy farts into someone's mouth.
"Kayla gave a snappy cassy to her ex-boyfriend after he fell asleep at the party. He woke up humiliated, scarred, and possibly the most turned off by a girl he had ever been."
by Hansonpaulsey October 14, 2009
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