[Here be spoilers, but mostly for Demon’s Souls and the original Dark Souls. Dark Souls II gets a lighter discussion.]
The warriors who entered Boletaria’s fog couldn’t find their way back out, and you’re just one of many to end up trapped there. It’s fitting to bump up against the edges of your cage. Demon’s Souls is self-contained and claustrophobic, with no true escape regardless of the choices you make or how far you progress. You can defeat the world’s demons. You can try to help people, or take on assassination contracts and start picking them off one by one. You might eventually gain an amazing amount of power but you’ll still be bound to the Nexus, constantly returning to this hub in an unbreakable cycle. It’s a sanctuary for many, creating rest and safety at the eye of the storm, but also a prison.