The Demon Prince goes to the Academy - Chapter 10

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

The fallen ones, strange monsters that showed up on earth with the sole purpose of destroying everything and ruling over humans.Only one man remained during the onslaught, his name, was Rashin Montero.“Do you wish to live or die?”The question appeared before him.“Kill me assholes!”He died.A hundred years passed and Rashin finds himself alive in the future.It turned out he was saved by a stray angel, and was granted a powerful energy that allowed him to stand on equal footing with the monsters that once wanted to take over earth.In his new future, the world has been restored to what it ones was, a huge shield was placed around the world to keep the Hakiaas out.Heroes were summoned to defend the world against these monsters during the Countdown, while the monsters could not be killed or harmed, they could still be sent back to their world.Or at least, until Rashin arrived.[Blacksmith System activated. Welcome host.][Initializing core functions... Complete.][Congratulations, you have gained a new blue paint (Large sword.)][Stella blade has passed all requirements to evolve.][Evolving to human form can now be processed.][Congratulations, you have gained a unique core, your weapons can now undergo fusion.]Having a system that allowed him to craft weapons of all kind, Rashin enters this new world trying to survive while also remembering part of his memories.Not just that, he can also turn every weapon he makes into beautiful overpowered maidens capable of killing the Hakiaas aka fallen ones.

I was forced to live in captivity for the rest of my life because I happened to be aware of the fact that I was a saint. I was truly a ‘real’ saint, but that didn’t matter, because there was already a designated saint in the temple.

When I died from all the abuse I endured, I was sent back to a time before all those previous events in my life had happened. After 15 regressions, I was exhausted. I prayed, “I don’t want anything to do with this, so please just let me die,”

And at that moment when I could finally be able to die, someone said, “How about being my daughter?”

…. That monstrous duke had adopted me.

Being given a chance and reincarnated is nice and all, yet why do I have to become that male friend who just watches the protagonist flirting with his harem?---World: Kaguya-sama: Love Is War - Hyouka ----