Demon Crystals

On the other side, they saw that the world they had entered was extremely barren. The typical Hell-like scene of fire and brimstone, with Demons torturing evil souls with glee was not present. 

After all, that was the spiritual type of Hell, and this one was more of a physical Hell. Demons were not evil beings meant to punish souls, but just another race who had adapted to their surroundings. 

Hell here was just a barren world with scarce resources, forcing its residents to adapt and become ferocious in order to survive on the little that was left. 

So the place they had appeared in was the plaza or town square of a Demon village, which had a weird style of architecture. The buildings were shaped like a mimicry of human style medieval architecture, just that the black material used, which was likely obsidian, caused the aesthetic to become far more sinister.