One-Click Upgrade: Super Decomposition System - Chapter 445

When Su Jiu dies on her eighteenth birthday, she transmigrates into a novel about painful love and becomes an adorable four-year-old child.

30-year-old Jo Minjoon has always wanted to become a chef. He started his culinary career late in life, however, and is currently chopping onions at a restaurant. Regretting his life choices, he wishes he could go back to change it all and falls asleep. Meanwhile, someone out there is willing to give him another chance and send him back in time. How will he use the new powers he obtained from this mysterious being?

Liu Yan, an ordinary office worker from Earth, unexpectedly traveled to a strange world.

The heroes of the ages are on the side, embarking on a journey to conquer the heavens.

- Description from novelbuddy

In the foreign world, the martial artists dominate the world and the sword of the emperor controls the fate of hundreds of millions of lives! Long Yu, the number one killer on Earth, after dying, takes rebirth in this new world in an aristocratic family of martial artists but faces rejection because he is unable to practice martial arts.