If someone has a bag on them, it means they're in a bad mood for some reason. It's a politer way of saying that the person has their "arse in their hands"
Mark: I just asked the gaffer if I can book a few days off work and he went absolutely ballistic at me!
David: Yeah, probably best to stay away from him today, he's got a right bag on him for some reason.
Doing coke, doing lines of coke
Me and the boys are gonna slaughter bags tonight post-bar
one who's nutsack is so big they can use it as a sail on a boat
we got off the island because it was windy and Gene was an old bag sailor...
Did you hear? Stephanie is renting out her sleeping bag for sausages. I can't wait to rent in for myself ;b
A sexual position that has the appearance of lifting of the rice bag
Person 1:My biceps have been getting a good work out lately.
Person 2:Oh you have been lifting of the rice bag with your lady lately.
The breasts of a woman who is lactating and/or breastfeeding
Look at milf with the baby stroller- she has the biggest picnic bags I have ever seen!
To not only skip out on your partner in crime so dat he gets da blame for your "combined" transgressions, but you also abscond with whatever ill-gotten booty dat said hapless cohort helped you to "acquire"!
In da "Adventures Of Huckleberry Finn" tale, da King and da Duke had both secretly planned to bilk da other out of da sack of gold --- i.e., each one of said selfish 'n' shameless shysters possessed da classic "no honor among thieves" mindset, and thus was going to pull da disgraceful "run off and leave him NOT holding the bag" on his unwitting accomplice!