[Protagonist Turns Dark] + [Demonic Villain] + [Neither Good nor Evil] + [Decisive and Ruthless] + [Absolutely No Saintly Heroics] + [Extreme and Bizarre] = [I Don't Even Know What This Is]
In the Yian Realm, any ordinary person whose dantian meets the required strength can open a Purple Palace through the formation at the annual Source-Opening Ceremony. Once they have chosen their innate Source Soul, they can become extraordinary cultivators.
Eighteen years after transmigrating, Gu Ansheng has always ranked first among ordinary people in dantian strength at the Source Master Academy. If nothing goes wrong, he is destined for a brilliant future after the Source-Opening Ceremony.
But with just one week left until the ceremony, something did go wrong.
The academy's number-one beauty, playing a round of Truth or Dare, publicly accused Gu Ansheng of groping her, humiliating him beyond repair.
Her cultivator fiancé then struck without bothering to learn the truth, destroying Gu Ansheng's dantian and completely stripping him of his chance to take part in the ceremony.
The academy used this as an excuse to expel him.
With all hope gone, Gu Ansheng returned to his family's old home in the mountains. There, he unexpectedly discovered that his late father had been the final patriarch of the Ming family, once the Yian Realm's foremost demonic cultivation clan, and had left him several powerful inheritances.
After taking over as patriarch of the demonic cultivators and claiming his inheritance, Gu Ansheng resumed his original name, Ming Ansheng. Using the space artifact Gu Soul Urn, he opened an Artifact Palace and, at the first heavenly tier, equipped himself with an innate Gu Soul that had lived for six million years. From then on, he would sacrifice the flesh and blood of countless living beings to attain the Dao through Gu!
“Human hearts have grown false, and the world has sunk into depravity. With blood Gu, I shall attain the Dao. All things are but dogs of straw!”
Gu Spring and Autumn
It's too wordy and contains too much unnecessary talk. Something that could be explained in one sentence takes more than a dozen sentences.