I'm sitting at the desk in the abandoned fiction department. This guy (early 20s Black guy with glasses, clean and well dressed but a little off-looking) starts walking around in circles pressing a button on his cell phone over and over to make it beep.
Beep Beep finally makes it over to the desk.
Me: "You need some help?"
Beep: "You're asking that because I'm Black, right? So because I'm Black I need help?"
Beep Beep goes on like this for a couple seconds getting more agitated.
Me: "No, I asked if you needed help because you're standing under a sign that says 'ask here.'
That short-circuted him and he went to the back to read comic books.