1) a bonus-feature in GrandTheftAuto 2 Multiplayer that gives you a little party following you around. They only disappear when shot by your opponents.
2) the situation when you invite a couple of friends to hang out, they call some of theirs and before you know there's the party of the year happening at your house.
a: dood, your place looks nuked!
b: ya, instant gang last night..couldn't stop it.