Hell's Handbook - Chapter 1: Hell’s Handbook

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

In a morgue filled with the bodies of Uchiha clan members, he opened his eyes...A mysterious voice echoed in his ears...With a bewildered expression, he muttered, “Save the Shinobi world? What does that have to do with me, a mere Uchiha survivor?”

After dying a pathetic death as an overworked office drone, I woke up reincarnated as Archer—the bastard prince of the Brutish Empire.My existence is a royal secret as My father, the King, would rather pretend I don't exist. My half siblings get royal treatment while I'm hidden away like a dirty secret.But I have a secret of my own. I was OP.By age two, I realized monsters flee from my stupidly OP mana. By age ten my mana could level cities—if I dare to unleash it.When my half-sister is kidnapped by the demon king, I finally decided to step out of hiding to become the strongest in this new world.

Xie Changgeng, the governor of Hexi, married Mu Fulan, the princess of Changsha.

Xie Changgeng, who had not even seen what his bride looked like on their wedding night, finally returned home after more than half a year only to find that she had returned to her parents’ home.

Although very dissatisfied, he could only chase after her.

- Description from Novelupdates