Of Demons And Ghosts (Demon Slayer and Ghost Of Tsushima)

The Fall Of Iyo And The Rise Of Evil

Long ago, there once existed a powerful onibaba that terrorized the spirits of Tsushima. She was a creature of hate and resentment that fed off of the death and suffering of the living. All she wanted was to breach the veil separating the living and the dead, and wreak havoc upon the people she despised so much.

This creature was known as Iyo. A priestess in life, she was killed by those she led, for they feared the effects of her influence. She and her child were buried alive, and she swore vengeance on the island. 

Unfortunately for her, she wasn't anywhere near powerful enough to achieve this. So instead, she waited, hatred festering and consuming her like a vicious decay, eating her until nothing but memories of her death and her promise of vengeance remained. 

Her break would come soon however, as Khotun Kahn would sail for the shores of Komoda Beach. He, along with his army of Mongols, wiped out the Samurai protectors and enslaved the island. Iyo could feel the despair of Tsushima's people, their fear, the pain they felt as they were shot, stabbed, burned, and she loved every moment. She delighted in their suffering as they had delighted in hers. Her power grew rapidly as she feasted on carnage, and she prepared to breach the vail. But to her unending frustration, her power had grown far too fast and showed no sign of stopping, and became too strong to escape without destroying herself in the process.

By herself, that is. So she began to build an army of oni's, giving each of them tasks to perform so that the veil could not only be breached, but completely shattered. The weak oni had just enough power to safely breach the veil, so they were given the task of hunting living twins on the island... and stealing the beating hearts from their chests. Iyo would use her power to tether her soldiers together with the twin hearts, giving them a life-force that could not be diminished as long as one of them still lived.

The stronger oni that were incapable of breaching were given a far greater task. They performed dark rituals to steal power from the kami's. The depowered kami's would stand no chance of stopping her, and her oni were virtually unstoppable.

But alas, these actions would not go unnoticed.

A group of spirits emerged. These were the spirits of fallen warriors, rising to fight evil once again. They fought relentlessly against Iyo's efforts. Breaching the veil and slaughtering the oni that hunted the twins, earning the blessing of the kami as they destroyed Iyo's rituals and empowered oni, and defending many villages from her continued attempt at expansion.

This group was known as The Ghosts.

Iyo's anger steadily increased as she sensed her army beginning to crumble. And she practically exploded when the power she had been cultivating began to stagnate and cease its growth. 

In the living world, there was one man at the front of her issue. One of the 2 samurai who had survived Komoda Beach.

Jin Sakai. Or as he was now known: The Ghost Of Tsushima. He had been leading an insurgence against the Mongols ever since he was pulled from the battlefield and nursed back to health. In his journey to kill the Kahn and take back his home, he began to fight differently, adapting to the Mongols. He used poisons, attacked from the shadows, opening his enemies throat's without making a sound. He abandoned the code he had lived by so he could save the lives of his people, giving them hope and becoming something more in the process. 

In the end, Jin had ended the Kahn's terror by taking his head. But his actions had made an impact, one that the shogun could not ignore. Clan Sakai was disbanded, and Jin was no longer samurai, but that hadn't mattered. He would do it all again if he had to. The part that did matter to him, was that the shogun called for his head... and called for his uncle, the Jito, Lord Shimura, to be the one to deliver it.