It's a knife. You use it for stabbing people. Although it might not be as pimped out and ghetto as the other weapons, it's more effective, which makes you more of a thug...I think.
You're in to brutally ripping apart people's faces with keys while they're down. No one knows how you got the key, cuz you're too much of a thug to own anything you'd need a key for. Oh well.
Hmmmmn its a tough one....My previous ninja training tells me nunchukas but I spose their not pimp thug now are they. So i'd have to go with the old trusty baseball bat, legal to buy, and if you happen to have a baseball cap on sideways you're gunna look like you're in the pros.