Gekitotsu no Hexennacht - Volume 2, Chapter 10: I Want To Deliver This

What if you could hack the strongest heroes and turn them into your devoted companions?Once feared as the Heavenly Demon, Zain stood above all—unstoppable, unrivaled, unchallenged.But his reign came to an end when so-called righteous cultivators banded together to eliminate him, believing they had purged the world of its greatest evil.Yet death was not the end.Reborn in a world dominated by heroes and champions of justice, Zain awakens a mysterious Hero Hack System—a power that doesn’t just defeat heroes but rewrites them.With a single command, he can shatter their convictions, twist their destinies, and rebuild them into something new.A ruthless warrior queen? Now a loyal blade at his side.An untouchable holy maiden? Now eager to obey.The strongest hero who once stood against him? Now kneeling before him, waiting for his command.With every hero he hacks, his harem of once-unshakable warriors grows. But as he reshapes this world to his will, one question remains—who gave him this system, and what price will he have to pay?They ended his reign once. This time, he’ll reign over them all.

Shao Xuan joins a friend in his expedition to a recently discovered archaeological cave. After he picks up an ordinary looking stone he is teleported to a different world and wakes up in the body of a small orphan child. The world he is in now is still in its stone age with primitive tools made of stone and the ways of the people are savage. Savage isn’t the only thing special about the people though, because they have superhuman strength, jump higher than trees and punch stones. In short, they are able to cultivate their bodies. Despite all this, it is a real struggle to survive because of the scarcity of food. Together with Caesar, his pet wolf, he tries to survive in this cruel world.

- Description from novelupdates

Three Days of Happiness is a novel by Sugaru Miaki, also known as Fafoo. It’s a rewritten version of the story originally posted to 2ch.

The premise of the story revolves around a shop where one can sell away the remaining years of their life, and the consequences of doing so.

“I Say A Little Prayer” is a short related story which was posted along with the novel’s release. It spoils some things about the main story, but nothing major.