That was hilarious. I honestly dont think the girl was a chick. I think you were jumped by 3 dudes. If she was a girl, she'd be offering more. But you cant tell gender from the mouth.

Happens a lot in Chicago.
Im guessing they do that to a lot of guys. Never walk with people when theyre getting in front of you and beside you like that, its a common way to trap you in. They were probably waiting for you to walk somewhere deserted. But since you walked away early, the "it" made a scene and they grabbed your wallet and ran. Consider yourself lucky.
Still a funny story, but it could of been way worse. Be more careful! Or at least carry something to protect yourself and know how to use it. Check you state laws for what's legal. Here in the city, 2.5" knives and pepper spray is the only thing, but every state differs. A roll of quarters works wonders too.
I walk alone a lot. And I used to work at night a lot, and come home anywhere from 11pm to 3am, many times on the south side. You see a lot of bad things. And learn a lot of ways to stay safe.