Denizens of Filth

From publisher blurb: The cities and towns of Rûl are islands of civilization that provide a refuge from the horrors in the uninhabited parts of the land. Behind their walls and barred gates, citizens feel safe from what lurks outside. Content in their homes, few of them realize that the tunnels and sewers under their feet teem with sinister creatures and foul abominations that wallow in the filth, looking for the right moment to snatch a fresh meal. One such terror is the creature that most people call the filth goblin. This offshoot of the goblin race thrives and multiplies in the fetid sewers, privies, and waterways that flow beneath the largest towns and cities. Their primary form of sustenance is humanoid waste—the warmer and fresher the better. Few citizens sitting down to do their bodily business realize that something sinister might lurk mere feet or inches away.