Mated at First Sight - Chapter 946 - 622

A boy from 21st century Earth, met an accident and later was reborn in Naruto’s Ninja World.
He is born in Uchiha Family and becomes the useless brother of Itachi Uchiha and Sasuke Uchiha…. Let’s see how he changed the Naruto 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.

After seeking pleasure in the nightclub and a night of romance, he discovered there’s a seed in his stomach;

I, Ichinosuke, failed to get a job for 100 consecutive times. Furthermore, my record is still being updated as unemployed.