She has a reputation for being 'good/great in the sack'. [=for being a good sexual partner]
He's ready to 'jump/climb in the sack' [=have sex] with any woman who'll have him.
The company 'gave him the sack' [=fired him] for improper conduct.
(..) Chinese? Thai, maybe? I've got it. Italian food. What's your name, angel? I want you to put the sack on the floor. Good. Now I want you to tell me everything you know about Italian food. Don't forget the name of the chef (..)1994 Léon: The Professional