MTL - The Alternate World Is Too Dangerous: I Hide In Reality And Rule! - Chapter 161 The greatest evil of human nature is

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

“Shit, is this really how I turn out?!”In the time of war he was known as the Body Flicker, Forbidden Magic Maker, and the Golden Blur.Arthur Vaelthorne.He had so many titles that it was unsurprising that the empire was the side that won the war, all because he had participated in it.A man that had the potential to become the strongest, rivaling the old powers, and the talent to back it up....Only ended up as a hidden boss in a popular game, meeting his end at the hands at one of his own students.A powerful hidden boss, unfortunately he had the fate of any other boss: Beaten by the protagonist.Now, with a second chance and the memories of one of the game's top players, he has a chance to rewrite his fate.

“This guy, how heavy is his taste, he’s still able to eat?” Waking up, she looked at her reflection in the mirror, explosive hair, tattoos, and a demon-like face. Look at her for more than a second and you’ll have spicy eyes (your eyes will bleed-aka she looks really ugly).

MC (female protagonist) dies in a plane crash and wakes up in the body of a beautiful but corrupt and lascivious prime minister in ancient times, Zhang Qinglian. As circumstances decree, he (she) cannot reveal that the original owner’s soul is gone else calamity might occur. So he (she) decides to walk a righteous path, determined to help the lovely but simple little emperor rule the country. Not backing down after facing torture, not losing courage, destroying rebellions and facing off with scheming princes.