Guardian Spirit Beast

Nen Beasts are Nen guarding creatures possessed by the Kakin King and the Kakin princes.

History
In the age of rival warlords, Kakin was a small country threatened to be absorbed by it's neighbouring countries, around that time the First King of Kakin conjured the seed urn inspired by the "worm toxin" and had his children fight in a succession contest which became the foundation for Kakin becoming the superpower that it is today.

The Seed Urn Ceremony
The ceremony to obtain a Nen beast, the host must offer a drop of blood and then insert their hand in the center of the Urn, a Fairy Like creature will then come out of the earn holding a gewel and insert it into the host's mouth.

Properties
Born from a deceased person's strong desire of perpetuation for their descendants, They possess someone related to the dead, feed on their aura and takes a shape and an ability influenced by the host, however since Nen Beasts are not a direct creation of their host, they cannot be manipulated at will. The Nen beasts are embued with instinctual rules to distinguish them from regular beasts: 1) Nen Beasts do not kill one another 2) Nen beasts do not attack another human whom a Nen beast is protecting