To Bewitch a Devil - Chapter 296 I wil kill him, myself

While returning home from a boring day of work, a black hole opened up in front of John and sucked him in. Before he was floating in the blackhole, a helmet latched on to him. "Uploading A.I under progress...Activating Survival Kit" A weird robotic sound appeared within the conscious of John and suddenly a white energy enveloped him... After opening his eyes, John noticed he was teleported to a whole new world. A world of magic and he was a user of a system. Arkon, the world John was brought too, was a medieval world which is 10 times bigger than earth. This new world held many new mysteries and this was the beginning of John's adventure. John will dominate and stir the world with his new system. Old technologies begone and use my advanced techys instead! Ha! you want to hold a politic, economical and military war with me? Sorry but my system is too broken for you all to counter.

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

Gu Yuanyaun had transmigrated inside a currently popular novel. She transmigrated into the body of a woman that carried the same name as her. Coincidentally, the woman already had four sons but was forcibly separated from them by an accident and ended up with a miserable ending.

As time gradually passed by, it was always accompanied by change. The four sons grew up and became successful individuals. They became the bosses on their own chosen fields while on the contrary, their mother, Gu Yuanyuan, instead turned into a teenager which was even younger than her sons.

Seeing that the hurdle was too high, Gu Yuanyuan, who became a pea princess on the story, decided to find her four sons.

The eldest son was a billionaire.

The second son was a legendary medical doctor.

The third son was a martial arts prodigy.

And lastly, the fourth son was a genius professor.

Gu Yuanyuan smiled with a kind face and said: “Dabao, Erbao, Sanbao, and Xiaobao. I’m your mother”

Looking at their mother’s appearance that could be mistaken as their own daughter’s, the four big sons was: “…???…”

- Description from Novelupdates

Summary Version 1:

The mysterious boy Ling Chen is saved by a little girl as he lay on the street dying. Years later, he strikes a deal to save this savior-turned sister and enters the virtual world. In a future Earth where advanced warfare has forced nations to settle issues virtually or else suffer the consequences, Ling Chen bursts into the scene and goes from unknown to legend. Yet all is not as it seems, for Ling Chen has a dark past, and there is a greater mystery at hand behind this virtual world.

Summary Version 2:

To save his terminally ill little sister, Ling Chen enters the newly released virtual game world and joins a small gaming studio comprising entirely of women. From now on walking upon his path towards the pinnacle. An ancient, evil item almost forgotten by history, the “Lunar Scourge” helps forge his unsurpassable legend, and causes him to unknowingly step upon a path that is destined to be punished by the heavens, the way of the shura.