The universe is a future where the cultural and biological evolution of the human race has divided it into two societies: "Gelacks"[1] and "Reetions".
[2] Gelacks are dominated by the neo-feudal descendants of an ancient bioengineering project that modified humans to tolerate reality skimming.
"Reality skimming" (also known as rel-skimming) is a physically and mentally strenuous method of faster than light space travel which underpins the economy and culture of the Okal Rel Universe.
[3] The Reetions are the descendants of unmodified humans whose social system depends upon transparency moderated by a form of artificial intelligence known as arbiters.
Okal Rel is the belief system of the bio-engineered sub-species of humans called Sevolites, comes in a variety of sects, and is based on the sacredness of habitat as the stage on which souls are reborn.