Lore

# **Kimetsu-no-Yaiba: Final Sunrise Lore**

## General Lore

Just as every tale has its end, it must have a beginning. . .

This is where our story begins.

The year is 1920, Demons lurk about threatening the lives of humans every night, it is up to the members of the Demon Slayer Corps to cut through the dark that demons hide within, and slay them.

But where did this all begin? Allow me to inform you.

Approximately 1000 years ago demons first began appearing, the enigma behind their creation is unknown even to this day, as they remain in the shadows, their identity so secretive that not even the earliest demons knew of their identity.

In defiance, a group of humans banded together in order to combat these creatures, creating the first breathing styles, and starting the Demon Slayer corps.

For the first 200 years or so, the demons were unorganized, mere creatures that would stalk and kill humans at night out of the pure instinct of survival. Until the Enigma behind their creation founded the first member of they’re “Family.” And what many consider to be the first “True” demon, Gozu.

After this, the demons hierarchy grew, as the twelve Kizuki were founded, and the ranks of Upper and Lower moons were put in place. The lower ranks change constantly, meanwhile the Upper ranks rarely do so, sometimes for entire centuries a time.

Over the years, the demons have begun to beat down the Demon Slayer Corps, overpowering them with their numbers and extraordinary otherworldly abilities. But perhaps this may change? Who’s to say, but one thing is for certain. . .

The slayers shall cut through the night in which demons dwell.

## The Demon Wars

The first war was a shock. The slayer corps was still as disorganized as the demons they had been fighting. Sure, they had ranks, but they went out alone or in small groups, never getting any formal training in tactics or fighting in larger groups. When the demons attacked in force, the small patrols found themselves overwhelmed in that initial spearhead charge. The demons they had been fighting were scouts, the real monsters biding their time and feasting in silence to build their strength while their subordinates took attention away from themselves. They came from the south and clawed their way up the country. Cities burned, thousands dead and thousands more reported missing. A decisive demonic victory, their expansion only halted because they couldn't support anymore forward charges.

The second war was far more equal. This was when the border between the territories was constructed, a great wall constantly patrolled by slayers both young and old which still stands today. The demons attacked in much less numbers than before, still being able to punch a hole through the wall before being driven back. Still, it was quickly repaired. Despite it being a slayer victory, it was an omen. Why had they attacked in so few numbers? Were these just scouts?

The third war was more of the same, an almost beat for beat repeat of the second war. However, a discovery was made. The small insects that often infested the wall- a menagerie of beetles, centipedes, and even ants- were the demon’s eyes and ears. Somehow, they could see through them, hear through them, spy through them. Wherever they swarmed, a spearhead force would come pouring over the wall again. Since then, the wall and every other demon slayer stronghold has had a strict no bug policy, going through any length they can to make sure they aren’t being listened to.

The fourth war, the most recent, happened about 70 years ago. It was during the war that the demons unleashed their greatest weapon, The Greatest Calamity, Gozu. Normally, the general would’ve led from the back as he had in the last three wars. However, by then, he had deemed himself strong and worthy enough to lead from the front. The 200 year gap between the third and fourth war had allowed him to gather an army large enough to rival the expanding slayer corps, and in a decisive strike like no other before it, him and his men took over the wall, forming it into a demonic stronghold where they could fall back and resupply when needed. The battles of the fourth war were on a scale the country had never seen, entire cities wiped out in the night as the slayers were pushed back and further back, the demonic armies spreading through the country like vines up a wall. Even as the numbers of his army dwindled, the firstborn son continued his warpath, up until the battle of Tamura city.

At Tamura, the slayers, in a rare partnership with the Japanese government, managed to fortify the city into a massive demonic deathtrap. As the invasion force poured over the walls, they were slaughtered just as planned. All except for one. The sword saints at the time led the charge against Gozu, and over the course of but a few minutes, they were the only ones left standing, the thin line keeping the beast from its prize. The fighting was brutal, with four of the six dying in the process of the fight. And yet, it was not in vain, for when the second to last saint fell to the beast’s spear, Hironori, the last of his rank, managed to slice the beast’s head off in a decisive strike. And yet, as he stood there, he watched in horror as it stood back up and socketed its neck back into place onto its body. And as the sun rose, it gave him one final cackle as it stepped through a portal back to wherever it came.

Days later, without Gozu’s direct leadership, the wall fell and came back under control of the slayers, leading the fourth war to be considered a pyrrhic victory. Ever since the battle of Tamura city, the slayers have vowed to, at any cost, stop a fifth war from happening, for it could lead to the end of life in japan as they know it.

## Slayers in Modern Society

At the very beginning of their training, a slayer must swear on life, honor, and material possessions that they will use their techniques solely for the eradication of demons and benefit of mankind. Any other use or leak of information, such as joining a military, giving it to a military, or any other adjacent action will lead to their direct death and the death of anyone they shared that information to. Despite being one of the most polarizing decrees by the sword saints, it has a purpose. Multiple times now the Japanese government has tried and failed to take breathing techniques into their own military training as to expand on their expansionist dreams, and multiple times now slayers have tried and failed to give them these techniques for large sums of money, property, or other possessions. The slayer corps does not fight with a single country, but serves all of mankind. With great power comes greater responsibility, a sentiment which has drawn them the ire of the government. Most slayers after retirement, if they do not wish to go into teaching new slayers, are forbidden for taking any combat roles still as defined in their many contracts. This has not stopped many slayers from using their techniques in the workforce, though. The superhuman abilities of the slayers are put to use in construction, farming, and other physically intensive fields of work. The corps is generally neutral to these pursuits, as long as they're helping their fellow man to no detriment to another.