The Side Character’s Hidden Boss! - Chapter 101 - My Teacher Is Here

only led to his death.But fate had other plans.Reincarnated as the son of the strongest being in existence, the Demon King. One might expect him to resist, to rebel against the Demon King and kill him once and for all.But why bother?Being the good guy led to nothing but betrayal and death. This time, he'll live for himself. Women, pleasure, power—he will claim it all, as any true demon would.

The leaves of the chess game beside Lanke, and there is no one playing chess among the old trees
Xing caused Tian Yuan’s first son, and then looked back at the vast mountains and seas
When he woke up, Ji Yuan became a half-blind beggar in a dilapidated mountain temple.
A real person has a sword and a magic stick has a mouth, which is the foundation for Ji Yuan to settle down in this terrifying world.

- Description from novelbuddy

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.