MTL - The Record of Unusual Creatures - Chapter 1720 Northern

This is a story about a badass,

A human from Earth is thrust into the [Hunter x Hunter] world, becoming the Zoldyck family’s defiant, red-eyed prodigy. They call me a genius and the rightful heir, but I say that’s Killua’s burden to bear.Armed with crimson eyes, and a subtle yet powerful system, I’ll rewrite destiny, upend the world, and embrace the chaos with a wicked grin.

Cut through the road of life and death with one knife, and Hanren slaughtered all those who had hearts!

…

I don’t want to be a knife, I want to be a knife bearer.

I don’t want to be a pawn, I want to be a chess player.

an ordinary person.

But he wants to live out himself in this world.

The unknown road ahead is slim, and the future is unknown; just walking step by step, before you know it, it is already a journey, and there is no world.

The thorny road, the red dust is far away; the clever move, the step is high;

Flatten the sea, turn over the rivers and lakes; clear the blue sky, hold the sword of heaven.

- Description from novelbuddy

Riku Barusak is a hard-working child. Despite possessing an innate superior physical strength and having withstood harsh training she fails to unlock her talent as a spiritualist. The failure results in her being thrown away by her family.

Abandoned, the only ones that extended a hand to her were the demons, the greatest enemies of the human race. Serving under them as a soldier she becomes a weapon of human slaughter, a fiend that should never have existed.