The Eight Spirit Kings And The Rogue

The eight spirit kings—the undisputed strongest and most talented amongst all familiar spirits—each ruled their kingdoms.

If a familiar spirit wanted to survive in Gomparo, they must swear allegiance to one of the eight and obtain their crest.

Otherwise, they would serve as nourishment for other familiar spirits, as they wouldn't be protected by a spirit king's blessing. 

This classification would deem them rogue spirits, under the agreement among the eight spirit kings, allowing anyone to attack and absorb their energies.

This forces each spirit to either pledge allegiance to one of the eight kings or risk random ambushes.

Despite its tyrannical nature, this specific agreement maintained order in Gomparo as only kingdoms that officially declared war could kill each other's subjects, potentially enhancing or diminishing their strength based on the outcome of the conflict.