Seo Jihun, a Grade 9 civil servant who only wished for a thin, long, and peaceful life.
However, after being stabbed by a malicious complainant and meeting his end, the place he opened his eyes to was none other than a martial arts world where martial arts existed.

Even there, he wanted to live quietly, but someone he should never have encountered appeared before him.

“Choose. Between dying here, or becoming this one’s disciple.”

An old man who immediately put a sword to his neck, his true identity was the Leader of the Heavenly Demonic Cult.
Thinking he must survive first to worry about the consequences, Seo Jihun, like crying while eating mustard, chooses to become a Heavenly Demon.

Originally a competent civil servant, he grows into a unique talent within the Cult using his powerful martial arts and outstanding wisdom, but—

Why does he keep getting more work? Why does he keep getting promoted?

His original goal was simply a ‘peaceful life,’ yet somehow, his second life is hurtling down the path of a Heavenly Demon.
Will he truly be able to find the life he wants in this world?