Taking place on the same planet as this https://www.furaffinity.net/view/61798003/

One of the issues that arose from all the layers of cities was what to do with the waste and garbage. The elites eventually decided on just dumping it all to the lowest level. Out of sight, out of problem. To them it was, but for those who lived there. They’d have to move, lest they die.

And so the once original city of the planet, now lie ruin under the filth that has been dumped from layers above. One of the animals living here being strange rodents, which had evolved thanks to the pollution. As it was either die or survive. They now scavenge the wastes for any scraps of food that might have been dumped down.

Despite the filthy conditions, there may be some who actually call it home. Though it’s probably because they really need to get lost.