I didn't see any post like this so I thought it might be fun if everyone shared a scary story that's happened to them or to someone they know, starting with me of course: I was up late watching some random stupid videos, I don't remember what ones. My parents had gone to bed (heavy sleepers) and my brother and sister were out for the night. From what I can remember it was probably about 2am. As I often do I took a quick glance away from my computer screen towards the television across the room to my right, in the periphery of my vision I saw a kind of black log like object, for the split second that I glanced sideways I didn't notice it, I turned my head back towards the computer screen, but about a second later I turned again and I saw a long black arm reaching through my grated windows grabbing a couch cushion. It was the arm of a suit blazer and the hand looked fairly discoloured from what I can remember. My instant reaction was to scream really freaking loud, the freakishly long arm retracted and I ran upstairs to an awake father, not believing a word of my story. I sleep every night not knowing who or what that arm belonged to. I don't have any proof that my story is true, but if you believe mine, I'll believe yours.
Well I'd tell mine but I was on #romulation at that moment, so everyone who was there will laugh at me if I'd post it here.
The real scary stories in my life don't involve the supernatural. How likely is it that your family pulled a prank on you and then pretended to be unaware?