Reminds me of a chest freezer we had in the garage for years. We had boxes piled on top and kind of forgot about it. One day we noticed it wasn't working - have no idea for how long, but it must've been months if not a year or more.
When we opened it up, all we could see was a pool of black liquid in the bottom, and the stench was overpowering. We donned huge rubber gloves and took turns holding our breath and scooping plastic bags out of it. One must've been ribs, because the only thing left was bones.
It was so bad, we finally gave up and closed it back up. A couple of weeks later, the county was holding a "get rid of your old appliance" day at the county fairgrounds. So I borrowed my dad's truck and we loaded the freezer up.
After waiting in line, we pulled up to the unloading area and a couple of guys jumped into the back of the truck to unload the freezer for us. Unfortunately, they were trying to keep things moving along, and as they slid the freezer out the back, they let it tip onto one end, and the door opened, letting out all that black liquid putrescence.
We were mortified, and as the two guys jumped out, we high-tailed it out of there.
True story.