The circle of migration: It flows and ebbs, controlling the number of souls in Soul Society. Phenomena and normality are constants in maintaining the fragile balance of this cycle, and it nearly is the perfection of any force. However, It has just one flaw: every one- hundred thousand years, two souls in the circle of migration both collide and become one. They are joined for an uncertain amount of time, but when they are in the process of the migration, they once again split apart, entering the soul society and ending up at opposite ends of the Seireitei. One side of the spirit takes hold of all the pure nature of the two souls, filling with light and goodness and becomes quite a pure being. The other half is left with a curse of sorts. That poor half's reiatsu is tainted, strong in evil will, and is actually half- human, half- hollow. More times than not, these two souls are found the nearly immediately after they enter Soul Society and are immediately eradicated by the Soul Reapers. The Soul Reapers are well aware of this happening and have taken upon itself to find the two Souls and get rid of them. Even though only one half of the soul is considered evil, it is nearly impossible to tell which half of the soul will end up being the benign half. That is why they kill both souls, for if the benign half were to realize its hollow power, then the effects of its wrath would be catastrophic. Only once in history has the Soul Society not found the two souls, and it was the first and only time. In that instance, the world was destroyed and all life died. The one evil soul is both human and hollow in one at the same time, living side by side. If the hollow half of the soul ever takes over like it did before…

The world will fall

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