Prius C Key Not Turning

So my girlfriend's Prius C isn't starting. We put the key in the ignition, and it doesn't even turn. When I depress the brake, there is a whirring noise in the front of the car for about five seconds (I guess that's the thing that recharges the batteries from braking). I tried jumping it with my car at the jump point under the hood, but that didn't allow the Prius to start.
The information screen lights up when the doors are ajar and the interior lights work. I went under the rear passenger seat, thinking maybe I should try jumping the battery down there, and decided to test the terminals with my multimeter. The battery registered 12.7V. I went back around to the jump point under the hood, and that one registered 12.5V. So that implies that the problem might not be the battery. And if not the battery, I'm stumped. The car is eight days old. We bought it, new, last Friday. So I just don't know where to go from here. I'm reasonably experienced with normal cars, but this Prius is a bit beyond me. Any help would be greatly appreciated.

 

That was it.
We had some friends over looking at the car last night, and one of them must've turned the wheel without the key in it. I actually just got off the phone with him, telling me that was probably the issue.
Thanks for the help.