Corpses weren't horrible, but they were always bound to be unsettling when gathered in large quantities.
According to Ruru's recollections, he had been trapped here for around one human year. The number of humans fed to him in that time was in the thousands. All of their half-eaten corpses had been stored right here, in this place directly below the city.
Atlas thought that it was something like a mass grave at first. It wasn't unexpected considering the other operations of the people who captured Ruru. The plague in the slums could also be explained through these bodies, as this location was roughly right under the slums.
The collection of dead bodies that were being affected by the energy of the Sacred Relic created a powerful harrowing energy that reaped lives.
'Then, all of the clues I received upon entering the realm have been solved.'