Edit: Okay, so the bat is taken care of.
This was our guest tonight:
We spent a good half an hour with the doors all open, turning various lights on and off, poking it with a stick, harassing it with a mop, this guy did NOT want to leave.
Finally, Talia called animal control (because our building manager was like "uhhhh, good luck!"), and three cops arrived at our apartment.
Honestly, those guys were more afraid of it than we were. Nonetheless, one of them put on some gloves and used one of our plastic bags and grabbed it. He took it out onto the patio and released it (because Talia told them I didn't want them to kill it). One of the three was this really tall black guy (named DARRYL, LOLZ!) who was terrified of the thing. I would go so far as to say he was skittish. It was loltastic. Bat gets 6 out of 10 for inconvenience, but 8 out of 10 for providing amusement.