Shadow Person
"I was living in a house in Laguna Beach that had been there since the 1920s. In its history, it had been a speakeasy, a brothel, and a house for smuggling illegal immigrants.
"One day, my new wife and I were having an argument. I can't even recall what it was about. She walked down the block to get a cup of coffee and cool off, and I was alone in the house. From my bedroom, I could look across the hall into the bathroom, then through the bathroom and down the other hall. I was standing at my dresser, and I just noticed movement out the corner of my eye, and looked down there.
"There was... and honest to god, this gives me goosebumps just typing it, 17 years later, a black figure. It was maybe three feet tall, and it was only vaguely humanoid. It looked like black scribbles, like someone had scribbled a human shape, but the scribbles moved, like electricity arcing, that's the best way to describe it. There was no sound that I could remember. I distinctly remember when I saw it I wasn't afraid, just like, WTF? Then it noticed me looking at it. I can't say it turned around, it just focused on me I guess. THEN I was scared. I didn't move, didn't scream, nothing; I was just frozen, because it just fking came at me, it RUSHED down the hall towards me.
"I have no idea what it intended, but as soon as it entered the bathroom, the door closest to me just SLAMMED shut on it. Then I screamed. I yelled for my wife. She wasn't home. I went outside, into the daylight, and didn't go back in until she got home about 10 minutes later."
- makeskidskill via Reddit.