I Became the Wife of the Monstrous Crown Prince - Chapter 108

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

5 years after the world changed, the final boss appeared.

One day, Song Shuhang was suddenly added to a chat group with many seniors that suffered from chuuni disease. The people inside the group would call each other ‘Fellow Daoist’ and had all different kinds of titles: Palace Master, Cave Lord, True Monarch, Immortal Master, etc. And even the pet of the founder of the group that had run away from home was called ‘monster dog’. They would talk all day about pill refining, exploring ancient ruins, or share their experience on techniques.

However, after lurking inside the group for a while, he discovered that not all was what it seemed…