He’s Using The 666MHz Frequency

(I’m at the till when a customer hurries over, looking panicked, and pushes several items at me.)

Customer: “I need to pay for these, quickly!”

(She looks behind her and I follow her gaze, but I can’t see anything odd.)

Me: *while scanning items* “Is there a problem?”

Customer: “Yes! That man over there, he’s acting strangely.”

Me: *going on alert* “Oh? Is he stealing? I’ll call for someone—“

Customer: “No, no! He’s demonic. I need to leave right now.”

Me: “Demonic?”

Customer: “He’s talking to himself and waving his hands. He’s possessed. I just want to get out of here and away from that demon.”

(I was still none the wiser, but I finished the transaction and the customer hurried out of the shop. A few minutes later I finally spotted the man in question… having an enthusiastic conversation via a Bluetooth headset, and decidedly not a demon.)