YOU are in Abyss, a city beneath THE CITY. In various locations there exist passageways to Abyss. Most open to the fringes of the underground, with one key exception: the entrance in THE CHURCH, which leads to Abyss' heart.
Therein lies a tightly packed network of slum housing, black markets, bars, brothels, nightclubs, casinos, and more.
Even so, with all the vices Abyss is known for, it is also host to various diverse places of worship, as well as an extenesive LIBRARY.
Just how far the tunnels of Abyss go beyond the center is impossible to say. When in its midst, though, the tightly packed lines of rickety housing and technology held together by whatever was availible seem to stretch on forever. Similarly, Abyss' date of origin is unknown, though rumored to have been created before even that which it is underneath.
Regardless of its true size or age, every imperfect inch of Abyss is held under the control of one GROUP, which is itself led by a secretive HEAD.