Now (If. by "Now", you mean somewhere around 10,000 A.D.):
To survive in The Cellars, you either had to produce something or you had to deliver something.
Whisper delivered shit.
Human. Animal. No better fertilizer.
She pulled six huge barrels of it along Rags Boulevard on a wooden cart.
Draped in layers of rags so that no one could possibly see her.
For all anyone knew, she could have been a man or a woman, a child or a grandparent.
She did everything she could not to be noticed.
Yet,
"That's a mighty big load for only one person," Crickley Fabler said. "It can't be human, whatever's pulling that cart. Wouldn't have the strength."
"Stop, Crickley," his mother said. She knew how he liked to stir up trouble.
"If it ain't human, what's it doing in The Cellars? Only humans should be in The Cellars."
"Ain't no law against..."
"There's laws and then there's laws. I'm going to go get a look."
"Crickley!"