This is a good foundation for a fun game, but it ends up feeling unsatisfying.

I think running backwards is too over-powered, since the monster is halted by the player's line of sight. Additionally, the monsters movement is too predictable, as you can easily lead it down a hallway by slowly walking backwards. The monster will stop moving, even when it's behind a wall, which I think is too powerful for the player. There's no tension driving the player to make frantic decisions, and thus the game feels less scary.

As soon as I abandoned keeping track of the monster, the game was a bit more scary since I couldn't predict which hallway the monster would choose to follow me down. I think the game would be improved by adding objectives that require the player to cross the map in a specific order, and maybe in quick succession as well. This would naturally allow the player to lose track of the monster and create tension from its absence.

I hope this game improves in the future, since it's only a demo as of writing this.