Someone at a party who is trashed beyond the point of sobering up before they go to sleep or passout. They tend to ruin things by saying retarted stuff. Not a good person to have at a party.
Anya: If I had a gun right now, I'd blow my brains out!!
A Juice Box is when you're plowing a chick in the poop shoot and you unleash all of your piss. And then you continue beating that ass to pieces so that piss sprays everywhere.
Motha fucka, I just Juice Boxed the shit out yo mom last night. The piss sprayed out so hard that I gave myself a golden shower.