I was Caught up in a Hero Summoning, but that World is at Peace (WN) - Chapter 144: Is a War About to Start?

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

Bestselling author Elias Vayne has spent years writing stories to escape the horrors of his past. As a child, he was the sole survivor of a massacre that wiped out his entire orphanage. He doesn’t remember how he survived—only that when the slaughter ended, he was the only one left standing.His latest work, The Arcane Academy Chronicles, takes place in Veylin Academy, a prestigious school of magic and combat. But one night, after finishing the final chapter, Elias wakes up inside his own book—not as the hero, not as the villain, but as an extra. Worse, he’s been reborn as Kael, the very same orphan who survived a similar massacre in the story.But something is wrong. The academy isn’t as he wrote it. Characters are acting off-script, unknown forces are rewriting events, and the mystery surrounding Kael’s survival mirrors the one in Elias’s real life. The more he tries to regain control of the narrative, the more he realizes this world may not be his creation at all.

In this fantasy world, music and aether rules all. However, there is constant threat of demons and natural catastrophes. The most powerful men are musicians who use music, alchemy, and spells to safeguard their homes. A young man who just wants to find his father and know why his family was exiled, starts his journey of becoming musician – a journey that leads him to the crown of justice and glory.We are born of aether, grow under aether and die as aether. Awe of Aether! – Holy Code.

As a transmigrator turned extraordinary creature of the human race, he found the world to be more colorful than he had imagined.To more easily access everything this new realm had to offer, he first needed a special resume. Then, he had to find the right place in a city perennially shrouded in fog to fill out an application, and the last and most critical step...— was to kill a chicken or catch a mouse.