The most striking feature of Hell is its "ceiling." Instead of a sun or stars, the sky is an endless, flat expanse of millions of uniform wooden doors.
The Transit System: Each door corresponds to a specific Devil’s life cycle. When a Devil is killed in the human world, they "fall" through one of these doors to be reborn in Hell. Conversely, when a Devil dies in Hell, they vanish through a door to reincarnate on Earth.
The Memory Wipe: Passing through the Door-Sky acts as a conceptual "reset button." Devils rarely retain specific memories of their previous lives, though powerful instinctual fears—like the sound of a revving engine—can linger across reincarnations.
The floor of Hell is a vast, perfectly manicured grassland that stretches to the horizon.
Abstract Landmarks: The meadow is occasionally broken by disjointed structures—clusters of white stone crosses, floating architectural fragments, or massive, unmoving "statues" of Primal Fear Devils.
Atmospheric Noir: Despite the green grass, the lighting in Hell is often described as sterile and cold, creating a "liminal space" feeling. There is no wind, no weather, and no biological life other than the Devils themselves.
Where a Devil exists within this landscape depends entirely on their power:
The Drifters: Weak Devils (like the Sea Cucumber or Tomato Devils) wander the meadows aimlessly, often falling prey to larger predators almost immediately after being reborn.
The Primal Territories: The most ancient and powerful entities—the Primal Fears—inhabit specific "zones" where the environment itself warps to reflect their name. The Darkness Devil, for example, exists in a state of absolute, light-swallowing void that even other Devils fear to enter.
Hell is defined by a unique legend: the Chainsaw Devil. Unlike other Devils who simply kill, the Chainsaw Devil possesses the unique ability to erase a Devil’s name from existence by consuming them.
The Sound of the End: For the residents of Hell, the sound of a chainsaw is the ultimate "Death" because it signifies a permanent end to the cycle of reincarnation.
A Changed Reality: Because of this, many things that once existed in the human world (such as the "Sixth Sense," "The Star that broke children's minds," or "Four possible conclusions other than death") have been completely erased from human history and memory because the Chainsaw Devil ate their corresponding Devils in Hell.