Both religion and magic believe in the existence of multiple worlds. One of these worlds is ours, the human world. Other worlds are peopled by spirits, gods and demons. Those worlds are unimaginable by man (and thus terrible).
Religion also has the concept of transgression or passage.
But, ordinary man only enters one passage, at death. He leaves
the realm of the living and enters the world of the dead. Rork
obtains the power to pass from our world to parallel worlds in Le cimetière des géants.
Hence Rork's no ordinary human. In La tache
we read about Rork: "an apparently young man,
whose birth wasn't witnessed by even the eldest inhabitants of
Alien's point". In Le maître des rêves he
concludes: "... that was the last time I saw my parents.
That was three centuries ago." And in Le prisonnier du désespoir
he reflects "I can't age".
Yet transgressing can be dangerous even to the highly gifted
Rork. The battle between Rork and Pharass, the guardian of the
Passage is central in the second bundle of Rork's adventures. We
shall not go into this, since this album will only appear in half