There was once a world apart from the one known to humans. It was a beautiful place, filled with joy, peace, and life. The King and creator of the Other World ruled justly and kindly, and all was peaceful for many years.
Eventually, however, the Other World began to deteriorate. It became torn by war and hatred, and slowly lost its beauty. It became a bloodstained world of despair and death. The King slowly grew weaker and weaker, but despite this he still held the incredible power that he used to create that Other World within him.
In his weakness, it did not take long for the King to be attacked by an entity known as Final, a powerful creature born from the infinite, raging Chaos that exists between worlds. It tore the heart from the King, killing him instantly, and fled with the powerful heart back into Chaos.
It is said that the one who can claim the power within the heart for themselves will be given an extraordinary strength, a power that could end existence itself if it falls into the wrong hands. And so, drawn by the immense wave of power given off by the death of the King, many supernatural beings from all over the Earth and the Other World traveled to claim the power of the heart for their own purposes.