The story takes place in a mysterious place known only as 'the city'. This 'city' exists in a country that's mixed with all sorts of places peoples and culture. Certainly not the author's lazy excuse to mix in lots of concepts he wants to.
It exists in a modern earth, similar to the one that we know. The city is split into four main sections, simply referred to by their 'directions':
The North - A colder, crueler region of the city. Not much is known about the area, and most of the inhabitants tend to stay to themselves.
The East - Can also be further explored to reach the Far East, which is something like a japanese-inspired area of the city.
The South - ???
The West - ???
There is also a main central hub for the city, where people from all directions often pass through or use as a meeting point. The protagonist, Alan, alongside his first companion, Liliana, comes from this 'central area'.
Places exist outside of this city, and they will come up later in the story as is necessary. However, the 'city' is one of the few places left on earth that still manages to stand even after the apocalypse.
It remains split and lacking unity...for now.
Another mystery is that, for some reason, nobody can seem to remember just how 'the city' was really constructed, even before the apocalypse...