I used to live in an old 1970's house that was built on an old air force base. I have had encounters before but not like the one I'm about to tell you.
It was around 1am and I was still up watching TV when I heard a faint noise. Thinking it was the fridge; I shrugged it off and went back to watching TV. 5 minutes after the first noise I heard another noise this time it was louder and sounded like some type of metal being scraped across the floor "that's not a fridge noise" I said to myself. I sat there on the couch unable to move because of how terrified I was waiting for whatever it was to make its next move. Suddenly it got really cold and uneasy in the house but I still couldn't move. Then something told me to turn around and look at the fridge which I did and right when I turned around a black pool surrounded the fridge and formed into a "black mass" or what you would call "shadow person" with no facial features whatsoever. It stood there for ten seconds and melted in the floor. The cold feeling went away but the uneasy feeling still stayed like something was still there with me.
This happened to me before but in different areas of my house but the same shadow doing the same thing.