Strange lady or a demon in a human Body?

A girl and friends were playing and this lady showed up. She was acting a bit strange...her voice was all twisted and cracky, it sounded like she was having a stroke! She wasn't. all the people in town was scared of her and the girl didn't know why. She tried to investigate with her friends and do research about the lady. Nothing, nothing about the lady...can you find out if she just saw something or is the lady a demon in a human body?