MTL - Eighteen Years Old - Chapter 93

He is a young man without a spirit root. It is believed that this denies him the chance at cultivation. However, a mysterious lady imparts a Supreme Demon Classic to him and from then on, he starts his path of cultivation.
He undergoes a total transformation to emerge as the most fearsome and powerful fiendish demon in his era, that even immortals and fiends are fearful of him, and saints are at his beck and call.
Mastering the Supreme Demon Classic is the turning point in his life. He is able to unleash his immense and divine power from within, illuminating the entire universe!

- Description from Novelupdates

When the stars all over the sky open a door on the ground, the disorder of the solar terms becomes pollution, which is a disaster for the world.

Season division came into being.

At the flick of the fingers of the Lixia Commander, thunder and punishment fell from the sky!

Tomb-sweeping Day ordered the master to kneel in front of the grave, and my ancestors saved me!

…

- Description from novelbuddy

'Confucius spoke not of the bizarre, the valiant, the rebellious, nor of spirits and demons.'This is the story of Mok Gyeongwoon, AKA the First Heavenly Demon - Cheon Ma, the forefather of the main character of the popular novel and manwha Nano Machine. This story is the prequel to Nano Machine, taking place 800 years earlier.

I was proposed to by the Final Boss.