Transmigration

Transmigration is a metaphysical anomaly that occurs exclusively within members of the human race. Due to the fact that a human being is essentially a living breathing chemical and biological chrysalis, they are extremely malleable and are therefore capable of being subject to spiritual transmigration.

History
Transmigration has occured in the human race for as long as they have recorded their own history. Though as of more recent cycles, transmigration events are extremely rare due to the poor spiritual and physical quality of humans, so much so that it has become mythic and unheard of within the modern age.

Overview
When a human is conceived of they are an extremely malleable existence. They are a are a living breathing test tube which countless different forces are capable of funneling through. Because of this fact many spirits that have passed away in ages long since passed attempt to attach themselves to a human being. This results in transmigration, which is not a far cry from reincarnation.

Known Transmigrants
Uub - Transmigrant of Majin Buu.

Kureno - Transmigrant of Frieza.