She's an evil spirit who tries to capture living humans and send them to the spirit world for unknown reasons only to be stopped by the Pokémon, Dusknoir and it saves the humans from their deaths like Conway almost felt off a cliff to Angie and Ash almost got sucked into the spirit world. The ghost girl got blasted by Dusknoir as she was sealed away in her own dimension as the cave entrance crumbled, preventing her from taking humans away to her world. This is from the episode, "Ghoul Daze!"
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