My Life on the Line (Rewrite)

Prologue

Demons. They prowl the land as soon as the sun sets and the moon makes its appearance. They hide within the shadows of the night, away from the shimmers of light.

These demons have been roaming the land for the past millennium. They have been terrorizing humans for the sake of their hunger and pleasure. It doesn't matter if you're a child, a teen, an adult, or even an elder. For very few demons care about that. To them, as long as you are human, you are food.

That was why the Demon Slayer Corps was created. To fight against demons who prey on unsuspecting humans. The Demon Slayer Corps was created around 20 years after the demons surfaced. The Master and Leader of this Corps? The Ubuyashiki Family.

Around 500 years ago, during the Sengoku Era, the progenitor of demons faced a man he never knew could exist. His name was Yoriichi Tsugikuni, the very first breath user who, coincidentally, also uses the first breathing technique. The Breath of the Sun. Using this breathing technique, the man managed to almost end the progenitor of demons. If only it wasn't for the delay in his attack because of a question he asked the progenitor.

Many years after that, the progenitor sought revenge against Yoriichi. He sought after his descendants, looking to kill them. However, to his dismay, he never found them. Only to find out later that the man never had a descendant in the first place. Nonetheless, he still wasn't satisfied until he found a way to exact vendetta. So he searched and searched, that is, until he found the Kamado family.

The progenitor of demons did just as he had vowed centuries ago. He exacted revenge on the unknowing family. Watching in a twisted sense of pleasure as he slaughtered them, colouring the house and the white snow of winter outside in a deep crimson.

And that progenitor's name, is Muzan Kibutsuji.