Chapter 391: Soul Affinity: Soul Mates (Part 3)

In the past, the existence of something as abstract as the soul of a person or of a living being, in general, was simply a theory; a sort of specter or energy that under a series of ideas or evidence not scientifically proven ended up becoming a mystery. However, with the arrival of the unknown entity called Soul Record, whose purpose was also a mystery, the existence of the soul in the body of living beings was immediately confirmed. 

The reason why the existence of the soul came to light was thanks to the mana that the seemingly omnipotent Soul Record awakened. When the mana awakened, the intelligent beings on Earth were able to sense within their bodies that diffuse energy in the form of a mist called soul.