Companion spirit fruits possessed amazing and life-changing effects.
Through mysterious means, Ves Larkinson and the researchers who worked for him managed to develop a tree that could grow fruits that magically enabled people to form their own companion spirits.
Not everyone obtained a companion spirit right away. Those with weaker souls only gained companion spirit seeds that needed to undergo a lot of growth before they turned into anything useful.
Regardless, many different people tried to figure out how the genetically modified trees were able to spawn these miraculous fruits, and how they worked so well on humans.
Virtually every attempt at reverse engineering them failed. Researchers from both the Red Association and the Red Fleet had tried to replicate the relatively simple biological structures of both the trees and the fruits, yet failed to gain the power to safely induce the formation of companion spirits in people's minds.