Bofuri (The Strongest Shield Of Tensura) - Chapter 45 - Forty Five

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

[By the Author that brought you “Martial God Regressed to Level 2” & “The Swordmaster Who Returned After 1,000 Years”]A year has passed since the world turned into one ruled by hunters, and suddenly, I awakened.But that’s not all.I possess an extra status window that even includes a built-in strategy guide.

In a world ruled by mana and bloodlines, John White was born with none.Reborn from Earth into a noble family, he became the forsaken son of a duke (a bastard) bullied by siblings, ignored by servants, and banished at fifteen like trash.Two years later, he's dragged to a mana mine to be quietly killed by his brother's lackey. But fate has other plans.Deep underground, an ancient abyss-grade ring awakens. It merges with Earth’s forgotten technology with the world’s magic. Fueled by pure mana, it unlocks the Black Hole magic, granting him power never seen before.From a worthless outcast to a terrifying Void Lord, John begins crafting magical tech tools that warp reality itself. His enemies have no idea what’s coming.Will he burn his past to ashes… or rebuild the world in his own image?