Fallen Angel's Harem in the Abyss - Chapter 32: Things that Bloom and Bite - 7

Humanity has been gradually transported to the Abyss by a bored god to compete against other races and monsters.The problem is… humanity failed. In a last desperate push the strongest survivors chose a comrade to travel as far as possible back in time.

Martial Arts Year 1. Cracks have appeared between Heaven and Earth, and terrifying foreign monsters have begun to invade the earth.

Martial Arts Year 100. Martial arts have begun to flourish, and human martial artists are clashing against the invading foreign monsters.

Martial Arts Year 200. Humanity is declining, foreign monsters are continuously seizing habitual zones.

Martial Arts Year 300. Lu Sheng crossed over. Moreover, he had access to memories from 10,000 years in the future.

“The Body Refining Technique from 10,000 years in the future. After more than 10,000 revisions, it’s a thousand times more effective than the one used now!”

“Martial Art Breathing Method from 10,000 years in the future…”

“Medicinal Pill Recipes from 10,000 years in the future…”

“The Sacred Martial Scriptures from 10,000 years in the future…”

Martial Arts Year 10,000. Humanity has gone extinct.

“The Path of Martial Arts had been honed to its pinnacle, yet there was no one left to inherit it.”

“I, Luo Sheng, am Humanity’s final Ember!”

In this world, orphans or just anyone without any hope for this world can apply to become a “walking target”. Their sole purpose is to be a practicing dummy for the students of the sect who train to become “Demon Hunters”. These students need “walking targets” to test their training on living, walking beings of flesh and blood.
In exchange, they will be provided with food & shelter.
Their existence value is lower than a slave, but if they manage to survive a few years they can receive a life long pension.

Xiao Han is such a “walking target”. One time he witnessed a powerful Demon Hunter disposing a demon. When the demon died, a fragment of the demon that managed to escape entered Xiao Han’s heart. No one saw that, and even Xiao Han himself only felt some discomfort for an instant.

But that thing in his heart soon gave Xiao Han visions, and the first one is of a cultivation method which allows Xiao Han to absorb damage to enhance his body. A perfect cultivation method for a “walking target”.

- Description from Novelupdates

Lin Tian, who had reincarnated into the world of One Piece ten years ago met Garp, who was on duty to eradicate pirates, and become his student.