A sexual act in which a girl is receiving head, and lets out a giant queef while she is smokin' crack.
*Joe is giving Brittany head*
Brittany: That feels so good..
Joe: What the fuck was that noise?
Brittany: I'm guessing it's a queef?
Brittany: Well must've been from that good ole' crack i've been smokin'
Joe: Oh shiiiit thats a queefkin.