MTL - Zhan Long - Chapter 24 Little pacifier

Zhou Donghuang, a man from the Earth, is able to destroy any planet in the universe without lifting a finger. His supreme will can sweep across the vast cosmos in the blink of an eye. And his immortal spirit can depart from his body and wander around the universe!

The sky was painted gray forever. The light of the sun was restrained. The darkness of the night was deeper than ever. At such a time, he belonged to a class people didn’t even recognize as ’human’. He was at the bottom of the social stratum, a slave. And when his only family was taken away from him... he no longer had a purpose in life. Yet, he clung to life because of his promise. And he set an impossible goal for himself, just so he’d have an excuse to live. When he finally reached a place he never expected to be, in pursuit of a purpose he expected to fail and die miserably trying to fulfill... he awoke to a night that would change his entire life. He was an insignificant fly, a mere speck in the destruction of the Empire. But he... survived. And, despite being a slave, he gained the blessing of a king. Or rather, the curse...

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.

I was proposed to by the Final Boss.