Many dabble with the Occult at some stage. Those travelled and wise to the world know that there is a darker, unknown side to life. Necromancers toy on the fringes of the Occult energies to fuel their art, and those of zeal and religious fervor occasionally succumb to the darker side of their faith. Demons. Devils. Infernal realms. The Weird and unnatural. Elder beings you dare not awaken. All are the domain of the occult. Come; stop wading in the shallows and plunge into the depths! Fall to the darker art and discover what the Occult Brotherhood has to offer.
A planet (or city, valley ect) where those who enter witness protection can escape old age and death itself, so they can live for centuries without aging-provided they maintain their cover perfectly. If they are outed by anyone or ever utter their true name, they age the number of years they have not aged since the day they entered witness protection (which might mean that they age centuries in seconds and crumble into dust and bone.)