Apartment
The apartment is where your critter lives.
Your critter can be interacted with in the apartment, and you can decorate your apartment with a variety of items.
Additionally, it contains diegetic access points for the dashboard, the vending machine, and the arcade.
The GUI overlaid on the apartment screen includes buttons to access the 3 care mechanics, decoration mode, and the menu.
Generally speaking, the apartment is the root of the game's state machine. All roads lead back to the apartment.
Exiting the dashboard will return you to the apartment, as will exiting the overworld.