I was doing some remodeling until I found this.
I looked around the internet and I haven't seen anyone document this yet.
A little context: I was playing Trepang2, a game that is still in development which has a demo you can play on steam (which is what I'm playing right now) and I was playing around with the cheats they have that you can unlock by playing certain levels on certain difficulty's. Anyways I was playing around with the inf stamina and TMod cheats when I came across a blocked off area with static as you can see from the video. I saw "him", I rushed to make video, now we're here at the present. Now I'm wondering, what happens when you get close to "him", or if you shoot "him"? Will it bring you to that one backrooms horde map in the Trepang2 version before this one? I dunno. That's why I'm leaving it up to you to figure it out. Besides, I'm too much of a baby-man to find it out myself.