Wolfram & Hart's Holding Dimension is a prison dimension where the Senior Partners place inmates whose fates have not been decided. This dimension can be accessed through an automated Camaro that drives itself to a portal leading to the dimension. This dimension resembled a United States suburban town and its sunlight did not injure vampires.
The Prisoners placed in this holding dimension are stripped of the memory of their past and identities and given new ones, through a necklace they are forced to wear and live the same day over and over. They wake up and spend a few minutes with a fake family, and then go down into their houses' basement, where they are tortured by a demon that cuts out their hearts. Afterwards, the wound is regenerated and the process starts all over again.
Once someone enters, the only way out is to pass through the Wrath; a portal hidden within the furnace of each house, and mystically bound to only be activated when someone is wearing the necklace, thus preventing escape for a captive.
Should someone attempt to escape the dimension by removing the necklace, all of the citizens within, as well as the basement demon, turn violent and attempt to kill the attempted escapee and his/her accomplices: placing the necklace on someone placates these citizens and opens the portal out of the dimension, thus ensuring that a captive always remains.
One way to escape was if a person could place the necklace onto the torturer demon it would itself become both resident and torturer forcing it to cut its own heart out over and over.