"The Smell of Filth"

Have you ever smelled something but was unsure about where it was coming from? The horrid stench floods your nostrils and makes you want to vomit. You walk to one side of the room, then the other. You find yourself at a loss. Then you hear the flies buzzing below you. It's coming from the floorboards. A dead body was buried right where you're standing.

Apartments aren't supposed to be in this bad of shape. The paint on the walls are peeling, the ceiling is caving in and cracking in some spots. The linoleum floors look like they hadn't even been swept in decades. They really couldn't have been bothered to clean this place up a little before selling it to me?
I thought about unpacking my boxes, but I wasn't sure I wanted any of my belongings touching such filth. I had to work hard to clean the place up.
Pulling out a broom from my stuff, flies took off flying in all different directions. The scent of the house was musty, like walking in to a used book store, mixed with a public restroom on a hot summer day. There was a little hint of spice in the air as well to make it slightly tolerable.
I tried sweeping away some of the dirt on the floor, only to find that it had settled over the years and was now caked in. I'd have to scrub the hell out of it. I grabbed a sponge and soaked it with some soap and warm water. I got on my knees and began to scrub. As I did, little pieces were coming up, mixing with the foaming water to create some kind of sludge.
As I scrubbed, I could feel that the floor underneath wasn't exactly unscuffed. It wasn't completely smooth, it had something etched into it. I rolled my eyes, of course, why would something like this be out of the question? There wasn't much that surprised me about this apartment anymore. I wouldn't even be surprised if I opened a door to find a wasps nest.
Continuing to scrub, a lot more of the dirt was coming up. I was starting to see the white underneath. I scrubbed and scrubbed for what felt like hours before the entire floor was clean. I grabbed several paper towels to wipe away the sludge to reveal the clean floor beneath. I was proud of my work.
Throwing the paper towels away, the writing etched in the floor was just legible enough to make it out. 'God Forgive Me' was what I saw. It confused me and had my blood run cold. What the hell did this mean? The previous owner must have committed some pretty dangerous acts before leaving this place.
No matter what it meant, it didn't make me any less upset that I had to be the one to uncover it. I knew I had to call up the landlord when the next morning comes.
I was hungry but still hesitant to unpack my belongings, so I decided to call in an order for some food to be delivered. They said it'd be roughly twenty minutes, so I waited. During the wait, I decided to do some more cleaning. After all, what would be the worst that could happen?
I made my way to the bathroom to see how horrible it would be. The place smelled like the pent up gas of a thousand people after the consumption of dangerous burritos. I had to hold my nose to bear the stench. I grabbed some spray from a box and emptied the entire can in the room.
As I attempted to leave, I caught the sight of something mixed in with the dirt on the floor. Was that blood? I followed the slight trail to the cabinet just below the sink. There stood the strongest stench. It the rotting corpse of a human. It looked fresh.