The Metalwood Saga / Reference Guide

Full-series spoilers

Mud and Vinegar

First appears in: The Metal Wood

Mud and Vinegar is the "starting position for new trashboys" in the Under, functioning as a massive latrine and waste processing area. The room is made of "cement" with "big pits [that] lined the floor... each maybe ten feet in diameter". It is a foul environment where "the whole room smelled like shit. Like literal shit". Waste is managed through "large pipes leading into those pits" and "big, corrugated off-white plastic pipe[s]" that produce a "horrible whining sound" and a "grinding sound mixed with a high-pitched scream" when the pumps are activated.

Contextually, this is where Phoenix was forced to work after being demoted from the killgirls. The room also features a "sewer release valve" or "maintenance hatch" that allows trashboys to clean the system—a mechanism that Phoenix and Beam later used to kill Quynn by drowning him in a "ten-foot pile of brown and yellow refuse".