Deep under the small palace that Reizei owns on the surface of the desert is the well hidden 'Barracks' where hollows are kept until they reach the evolution of an Arrancar. While to most of the Espada and their forces it is known as the Barracks, to anyone ranking higher than Reizei, they know that it is in fact a death camp used to speed up the production of Arrancar under the control of Sestran. Reizei has kept the true nature of this place a secret from anyone lower rank than him to avoid any negative feelings between him and his fellow Espada, since it was a cruel way to treat any living creature. It looks much like a vertical city, created in cracks of the land that Reizei made by smashing the surface of the hardest parts of the desert, it's run by about a dozen weak Numeros that Reizei has kept under his control making it so he only comes to check up to make sure that none of his Wardens have died. Him and his wardens force anyone who is living in the Barracks to swear loyalty to Sestran in order to be free, and when they do they are greatly rewarded, but until that happens they are treated as if they were animals on a farm, waiting to be slaughtered.
