It is an upscale inn and meeting place for the city's elite, where they can chat and have a drink. The citizens can order mineral water, distilled water, sparkling water, synthesized alcohol derivatives H and T and the extremely popular Alcohol-Z mixture.
The bartender scoffs at real alcohol, dismissing it as disease-ridden poison. A wealthy and patient traveler can order a lot of Alcohol-Z and, depending on their Luck, can get either a bonus or penalty to their hit points.
In one of the bathrooms a most amusing character stands, the peeing man, who suffers from severe inability to urinate, leading to amusing exchanges when the Chosen One decides to interrupt his efforts.
The Parlor Room appears only in Fallout 2.