Kingdom Hearts III: Essence of the Heart
Prologue
When the heart is consumed by darkness, a creature known as a Heartless is born. If the person whose heart is lost has a strong enough will, another creature is born. The hollowed body, controlled by the soul, becomes what is known as a Nobody. But what binds the heart to the body? Whatever it is, it cannot take on its own shape when the heart and body are separated… at least by itself.
In rare cases, these mysterious bindings may meet with those of others. When enough of these bindings join together, the strongest person's bindings may manifest into human shape. These beings are known as Essence Links.
Essence Links are low in population, due to the rarity of these unions. These oddities can feel, just as we complete beings can, but these warped emotions only increase their level of threat. They feel that they only exist to complete others, and are drawn by the desire to be true beings. Unlike the Heartless, who instinctively seek out hearts with no true intention, or the Nobodies, who wish to complete themselves through collecting hearts, Essence Links have come up with one belief.
If they are the only ones in existence, then they must be the truly complete.
In a dark dimension, opposite ours, the few of these beings have gathered and plan to carry out this twisted crusade.