Shinji Matou at Your Service - Chapter 1007: Seen Through?

Coincidentally, indoorsy-guy Zhang Yang went to the cultivation world, being the lowest level of zombie. By using a manual book named: “ Tai Yin Refining Figures”, Zhang Yang find his own way to success and leaves a “If a zombie knows how to use a manual, nobody can stop it “ legend in the world.

- Description from Novelupdates

Marauders shot Yuan in the head and buried him in a ditch. They thought it would be enough to put him down. They were wrong.Rising from the dead by the will of the Gun, demigod of revenge and firearms, Yuan only has one goal in mind: track down his murderers across the Unmade World and slaughter every last one of them. With the bullet-core stuck in his skull marking him as a Gunsoul, he can finally teach these arrogant cultivators a lesson they’ll never forget.But revenge isn’t so easy to claim. To carve out a path through the wasteland, Yuan will have to face power-hungry sects, nuclear cultivators, and weapon-gods. Let them come. No one will bury him again.He’ll give them all a taste of Bullet Hell.

A skilled but unfortunate modern-day assassin was killed in a freak accident. However, he soon found himself summoned to another world by an evil wizard, who had him possess the body of a boy as an experiment. After successfully planning the evil wizard’s downfall, he used the wizard’s body as a springboard to gain influence and power in his new world.

- Description from Novelupdates

This is a story that follows the courtship between a stone from Hell and a god from Heaven that begins in the underworld and spans for three lifetimes in the mortal realm.