It is an underground area found beneath Tel Fyr. This is where citizens affected by Corprus can go to live with other similarly affected people. Victims of this horrible disease are usually sent here by the Tribunal Temple.
Divayth Fyr works here, experimenting on the victims of the disease in hopes of finding a cure, although he is not found here during the course of the game. His "daughter" Uupse Fyr, however, is found in the Corprusarium Bowels together with Yagrum Bagarn, as she is the chief caretaker of the patients. Patients can be heard to express their gratitude for Divayth Fyr's efforts to relieve their suffering.
Vistha-Kai is an Argonian knight and former slave who acts as Warden of the Corprusarium. He will allow the Nerevarine to explore freely, provided they do not attack or harm any of the residents. Among those living here is Yagrum Bagarn, the last known living Dwemer.
The Corprusarium is also where Divayth Fyr stores some of his treasures. According to Vistha-Kai, he lets thieves try to steal them for his own amusement, as to do so a thief would need to get past not only various traps and the guards, but also the diseased and dangerous patients. Those dwelling in the Outer Corprusarium will attack on sight; however, inhabitants of the area known as the Corprusarium Bowels will only fight if provoked.
The first section of the Croprusarium reached from Tel Fyr. It is made of tunnels dug into the ground. This is where Vistha-Kai can be found.