One Piece: My Crew is from Other World - Chapter 64 – The Dragon Guards Are Coming!

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

Cen Shuang used to be the daughter of a wealthy family. After she fell from grace, she was forced to bend her back just to make sure she had enough food. She was sold by her uncle for 10 million to the wealthy Zhuang family as the bride that would counter the bad luck in the Zhuang family.

She married Young Master Zhuang, who went into a comatose after a car accident. Everyone viewed the marriage between the fallen daughter of a once rich family and the comatose young master as ridiculous.

The socialites who were once under Cen Shuang’s feet were all waiting to see Cen Shuang make a fool of herself. Unexpectedly, on the night of their wedding, Zhuang Hong, who was in a vegetative state, suddenly woke up.

Cen Shuang instantly transformed into the Zhuang family’s benefactor, and the Zhuang family were extremely protective of her as they doted on her. Grandpa Zhuang asked, “Lil Shuang’er, do you want a black card?”

Mr. Zhuang asked, “Lil Shuang’er, are you bored staying at home all day? Should I give you a company to toy around with?” Mrs. Zhuang said, “This is the newest season’s haute couture. Throw those in the last season away since you’ve already worn them.”

Zhuang Hong, “Nothing about my wife concerns you!” From necessities to food and accommodation, the man did everything himself and spoilt Cen Shuang to the extremes.

Outsiders were jealous of Cen Shuang’s good fortune, but little did they know that this joyous occasion had been long premeditated. Zhuang Hong, “A single look lasted for ten thousand years. After many twists and turns, I finally married the girl I like.”

Cen Shuang, “I thought that there will only be darkness in my life, but there’s a silver lining waiting for me.”

Let someone else go to war, you, lucky Austria, go get married! What the god of war can give you, the god of love can also give you.

The smoke of the Napoleonic Wars has dissipated, and the Vienna system that once brought peace to Europe is riddled with holes. Beneath the seemingly peaceful appearance, there is a vortex of the times with undercurrents, the tranquility before the storm.

The air is filled with the steaming mist of sweat, and the choking black smoke makes it hard to breathe. On the elegant dining table, a group of soldiers and fat men in suits are pushing each other, feasting on the feast called the world, hanging on the wall Van Gogh’s self-portrait with waltz in his ears.

Suddenly the music turned into a march, and the picture also turned to the battlefield. Soldiers marched in a neat line, walking towards the machine gun barbed wire.

A shell fell on the ground, and after the smoke passed, countless cavalry rushed to the artillery position.

Accompanied by a loud noise, a wooden plane flew close to the ground, then pulled up rapidly, broke through the clouds, and shone brightly.

- Description from novelbuddy

The Jiuzhou Continent contains an era of chaos and fiendish demons, haunted by mysterious beings and fraught with feuding martial families, demonic sacred grounds, and endless struggles between various powers. Conflict is a constant throughout the world.Within such darkness, Gu Chen opened his eyes to this reality.At the same time, he discovered that as long as he slew these fiendish demons and ghosts, his cultivation strength could continually elevate.Killing a Panic Level Demon yields a decade's worth of cultivation.Slaying a Ghost Level Fiendish Ghost brings thirty years of cultivation....Eventually, one day, staring at the endless swarm of fiendish demons and world-renowned grandmasters in his path, Gu Chen chuckled lightly, “Are you able to withstand this fist of mine, charged with 1600 years of cultivation?”