The Scarlet Fog is a multi-room pleasure house built around intimate chambers, bathing areas, lounges, service spaces, and narrow corridors. Curtains, beds, furniture, and interior partitions create a dense floor plan where privacy was part of the original design, while visible disorder and signs of violence turn the same architecture into a tense search environment.

For a GM, the building naturally supports uncertainty. Characters rarely see more than one or two rooms at once, curtains and doorways conceal movement, and the many small chambers make it easy for witnesses, clues, or threats to be separated. A second level extends the investigation without changing the building's character. In Shattered Star's The Asylum Stone, the Scarlet Fog is part of the adventure's city locations. Elsewhere it can be a bathhouse, brothel, exclusive inn, private club, or urban crime scene where the maze of rooms matters far more than the size of the building.