The Erebus clan was an imperial clan that adopted a few meritocratic practices.
There was a main royal lineage, their son automatically becoming the Heir upon birth but right after the heir were the princes and princesses of the clan.
They were called the Noble holders.
Before Orion's birth, the clan had nine Noble holders, each more talented and more powerful than what most could imagine.
The base requirements to become a noble were simple yet cutthroat and elitist.
Firstly, one had to be the direct descendant of a Pillar or Ancestor of the clan, this already weeded out most of the clan members as such powerful beings barely had any progeny, despite their long lives. After a certain level, reproducing was simply too complicated and risky.