Finding the dog is the main objective of the game.
The dog appears to be a female Corgi, and a service animal, has brown fur, with white fur under their body.
In certain areas, the player can whistle in order to locate it.
When the game starts, the player is walking the dog when a storm comes, and the dog is taken down the storm drain, forcing the player to go into the sewers to save it.
The dog is then seen after the player encounters the first enemy. It is then dragged by an unseen force through a hole, making the player progress through the sewers. It is seen again in the subway, unwillingly leaving with Virgil.
It is seen then in the laboratory, where it is washed again when the player opens the flood gate to escape.
The only creature in the mines mimic's the dog appearance, attacking the player when it gets too close.
It is possible to trigger a secret ending by shooting the dog during a nightmare section in the sewer entrance just before the player starts the lost tape#1
The Dog is modeled after and voiced by Dani, a corgi belonging to the YouTuber MrKravin. Although it has a tail, most Corgis have their tail cropped when they're young, and some are even born without them.
The name "Dani" is confirmed by Steam card, and the dog's name tag.