Super Invincible Upgrade - Chapter 1 -

Ruel finds himself thrust into a brutal post-apocalyptic world, bound to a bizarre “Milf System.” This system demands morally questionable acts – NTR, seducing milfs, and claiming other men's wives – as the sole means of gaining strength and essential survival skills.The brutal reality of this new world awakens Ruel's hidden lust and dark desires. He swiftly abandons any semblance of morality, embracing the system's perverse demands with growing fervor.Driven by an insatiable hunger for power and pleasure, Ruel revels in the ravages he inflicts, using his newfound abilities to dominate and conquer.His journey transforms him into a ruthless force, where survival is intertwined with the satisfaction of his darkest urges, leaving a trail of broken relationships and conquered women in his wake.

Kael, a reclusive and antisocial man, died alone in his apartment, consumed by frustration and regret. But his tale didn't end in darkness. Reborn in the unforgiving world of Eridoria, where the law of the jungle reigned supreme and apes were eerily absent, Kael found himself in the body of a lion cub with a unique bloodline.This was no ordinary rebirth; he was a lion unlike any other. Thrust into the complex web of pride dynamics and social hierarchy, Kael must navigate treacherous alliances, rivalries, and his own primal instincts. With a fierce determination burning within, he sets his sights on a singular goal: to claim the title of the ultimate King of Beasts.Warning: R18, incest, harem, neutral MC, violence.

He became a teacher at the best magic academy in the empire.
….For being mistaken for someone else.

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