Concept work for the underworld (hell) in my comic story
I think the underworld, where all the demons live, is like earth. The difference is this world got no colour, grayscale with only a slight tint of blue.
This is Furfur's place. I imagine him being a bit like Da Vinci. Although he is a high rank demon, He likes to experiment and create weapons. His hut is made of old wood and he likes to collect any materials he finds. Above him are thunderclouds, so he is in his element.
Time of speedpaint: 1 hour