This is one of my favorites by Ray Bradbury. Although it’s not written in the first person, we wonder if the main character’s friend may be an unreliable narrator—until things take a stunningly original, bone-chilling turn. What’s interesting is that the story is mostly rendered in dialogue, which parallels the nature of the very antagonist itself; the tension also ratchets non-stop. If you like refreshingly different, this one’s for you. You can find it in his fine collection October Country here: https://amzn.com/034532448X
For an early-winter chill, read Matt Hoffman’s “Bro,” now up at Read Short Fiction: http://www.readshortfiction.com/2011/11/bro-by-matt-hoffman/
If I make any comments about this story, it will spoil it. What I will say is that if you enjoyed Poe’s “William Wilson,” and the last scene in Drag Me to Hell terrified you, then you’ll get chills reading this. If you’d care to know why I loved this story so much, my comments appear at the end of the story.