A term used to describe the sexual act of dipping one's own nutsack into a toilet filled with bean burrito-induced diarrhea, and then allowing one's sexual partner to clean the fecal matter off of the scrotum using their tongue.
"Come on, nasty sack!"
"I still can't get the taste of Gud's diarrhea out of my mouth. He gave me a nasty sack last night."
Bag lunch, usually consists of two warm bologna sandwiches, a bruised apple or orange, and a small bag of regular chips. If you're lucky you might get zebra cakes, all in a brown paper bag. Most of the time sandwiches go in first so they get smashed.