Constellations were very powerful entities. They were boundless in terms of the branch differences, and their varying resonance.
In the eyes of the Constellation, they were in one and all of those branches at the same time.
Which then begged the question;
Why would such powerful entities be Familiars to weaker Vessels?
No one knows for sure. Perhaps it was just in their nature— to search through the Branches for worthy candidates that would inherit their powers.
Of course, their standards were completely arbitrary. It was up to them, and no one else, who they chose... and who they ignored.
Ah, yes, a Constellation could also have more than one vessel.
Unlike the other way around, where humans could have more than one Familiar, these amazing beings could have more than one host.
Considering the vastness of the branches, and the nigh infinite number of worlds that existed, that much was reasonable.
