An anal queef is the release of air from the anus after the penis has been removed from the anus after anal sex. Not to be confused with a common garden fart.

Briefly, "the realization that each random passerby is living a life as vivid and complex as your own." Originally from the Dictionary of Obscure Sorrows, which has a lot more beautiful neologism definitions like this you might enjoy.

when the fart is so soft it’s like a queef from ur butt

air excaping your ass like a vaginal fart