Petscop is a faux-PlayStation exploration game, in a similar vein to Yume Nikki. When started, the game shows a splash screen for "Garalina". The copyright listing on the title screen also says "© 1997 Garalina".
Something about Paul's mother having had it in her attic for years?
Note included with the game
The note that I found with the game:
I WALKED DOWNSTAIRS AND WHEN I GOT TO THE BOTTOM, INSTEAD OF PROCEEDING, I TURNED THE RIGHT AND BECAME A SHADOW MONSTER MAN
Please go to my website on the sticker and also go to roneth's room and press start and press down down down down down right start
Real or fake?
Petscop is not a real PlayStation game. The game demonstrates capabilities far beyond what the original PlayStation was capable of, and an absence of its limitations. The game features very precise real-time lighting effects, and does not exhibit the problems that would manifest from the PlayStation's lack of floating-point precision or perspective correction. The color depth is also too high to exist without heavy dithering.
It is very likely, if it is a game, to be written in a modern engine (such as Unity), rendered at a low resolution with NTSC-like shaders.
The Sony and PlayStation logos in the beginning of Petscop 1 were spliced in to help the illusion.
Twitter account @Petscop
The Twitter account is fake. Someone figured that Petscop was going to go viral, and squatted on the name. This is generally known as gamejacking — someone other than the storyteller attempting to interfere with the story. So far, there is only one tweet, though.
Petscop was originally posted to Reddit's creepygaming subreddit, by a user who had just registered and has not posted anything before or since. It is likely the author, "seeding" the story. There doesn't seem to be any other points to who is behind the story.
Some fans suggest that it might be "Night Mind", a YouTube commentator on horror/creepypasta games, who has said that they were "working on a project" and "wouldn't tell anyone they were behind it until it was over". Night Mind has stated they aren't involved at all.