How I see geographical logistics of the Hell in the Constantine film is that it's the aether ("The Selvage") between "Earth" and Hell; as a dark reflection and an incomplete physical transition to Hell.
The novelization clarifies that the Hell that Keanu's Constantine saw was a dark reflection of our world; the space inbetween spaces. Demons look like demons because, according to the film's Bluray/DVD extras, and to an extent the Lucifer show (i.e. Maze's zombie face in the mirror), Demons are vain and will see their true forms in a reflection. Imagine that, but as a much, much larger reflection.
It took Keanu's more 'grounded' Constantine little-to-no effort to reach that layer of Hell. But he hadn't fully reached that physical horizon.
John Constantine of Earth-1/Prime, with as much knowledge of the mystical sh*t he knew about including going to other Earths, took him A LOT of effort at first to reach Hell.
Entirely. Demons don't look like demons because when you reach Hell to it's fullest extent, they look human like us. (Depending on the class of demons, since some still look like hybrids.) That reflection is no longer there, thus there is no vanity...also because actors without make up is cheaper, but my point still stands since we still saw some with horns and raw skin like this guy:
Tiberius is Astra Logue's personal accountant. At some point, Tiberius became Astra Logue's personal accountant at Brimstone and helped her manage the place.[1] When Lachesis used her shape shifting to take the Encores, Astra discovers it and in a fit of rage injures Tiberious by throwing a...
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In other words, Keanustantine didn't make it far enough to transition completely to Hell, Earth-1/Prime's Constantine did however with added skill.
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