The sound made by a loose vagina queef.
Dude, that girl's vagina just went blumpff.
A qweef from the anus caused by too much anal sex; therefore creating a loose asshole where air can not be contained. So during anal sex, after, or just random blumpffs that are unable to be contained.
I had no idea too much anal would cause me to have so many backdoor blumpffs.