>>5218545I feel like Hell the Underworld are not very separate. Compared to Heaven at least, which definitely seems like its own realm.
The two below the human world are more connected but the Underworld is not an inherently bad place to be. Mori being a high-level Reaper should be able to go pretty much anywhere if she gave a reason. Maybe she's even been offered a transition to Heaven but didn't feel comfortable
She'd rather kick it in the dungeon. 