Ah, the ol' attention leech.

We have a couple of regulars who do this sort of thing regularly. There's a tall, fat, perpetually-sweaty-even-in-winter guy who comes into our store and close-talks at you without giving you an opening to end the conversation. He doesn't take hints. He doesn't stop even when you ask him. We're this close to banning him from the store, because he constantly interrupts our work at all hours and never buys anything.

Then there's a woman who will ask you about a product and then launch herself into a half hour-long story about that one time she went on a trip to Somewheresville and then she'll talk about the time her daughter went on a trip to Whogivesafuck. She'll talk to you until you cut her off with some task that you tell her you have to do. Then she'll wait for up to an hour for you to finish that task. Then she'll start up again. My coworkers and I have secret code for when she's in the store. We scatter like cockroaches.

The other one goes from door to door in our shopping center and just talks at people until they start to ignore her. First time I saw her I was amazed at how rude everyone was to her. Then I gave her a moment of my time to talk to her... oh god, that was a bad idea. She opened up the flood gates and followed me all over the store for half a shift. No filter, no reasoning, just a steady stream of consciousness. She left when I told her firmly that I have a job to do and she is directly interfering with it. She left crying and went directly to the next store to find someone else to latch onto.

Another regular I've learned to keep a wide berth from was truly certified. He came into the store like any old customer and was very friendly and charming like any old customer. He asked questions and responded and seemed pretty normal. He told me about this book he was writing while we talked about the products on the shelf. About five minutes into the conversation I realized that, wait, this guy isn't writing a book at all. This guy is schizophrenic. He thinks that real life is the book that he is writing. I realized that he had been subtly narrating the whole interaction, including his inner monologue. This became glaringly obvious when I told him that we didn't have a product that he was looking for and he said, "and then I became angry," out loud. The look in his eyes was suddenly quite terrifying. I placated him by telling him that we would try to order that product for him and sent him on his way.

Working a retail job is like playing the wheel of fortune, where the best outcome is that you get to talk to someone who is courteous, curious and patient. Every other spin of the wheel is a punishment of some sort.