PUNCHESCO, THE INIMITABLE

You'd be in a dark little dingy cabin that's one of or maybe the last place that's not completely overgrown by a horrible black mold growing on every surface and living being outside your door. Every day you have to make sure your perimeter is safe and clean the house and feed yourself from your giant pyramid of cans of tomato paste

There's some creepy thing that's watching you from the shadows inside the house. It is never addressed by your character.

Periodically survivors will come to your house, at first they're begging to be let in, but eventually they're just banging on the door and gibbering, corrupted by the mold

Eventually after a few days, despite your efforts, mold starts creeping down the walls, and soon it covers more and more of the surfaces in the house, sucking at your boots like mud and slowing down your movement