Based off of a mental image from my childhood, being in the basement of the home I grew up in with my dad as he's listening to his records. Running with the Devil by Van Halen used to scare the hell out of me when I was very young, and when I try to think back to why specifically, I get the impression of this...

Look out the basement window to the back yard, small lights begin to fall from the sky and swarm to the yard. A humanoid figure, made entirely of flame fades into existence. It's flowing, smooth movements mesmerizing, calming, distracting. You don't realize it's moving closer until it's almost at the window, you feel it looking in. It's unknown, gaze staring through you, probing the very depths of your soul...