Legend of the Cyber Heroes - Chapter 34 - Dyson Principle

A dancer who was killed by a serial murderer found himself occupying the body and taking on the life of Brian Morse, a patient with anti-social personality disorder. As Brian, he has the look, he has the brain, he has the charisma, but he also has something that somehow always attracts psychopaths…[The story mentions 3 reality shows and crossovers with the American drama series Dexter. SLASH]

- Description from Novelupdates

Dual cultivation isn't a choice; it's a necessity.

After being struck by a truck like most lucky protagonists (or unlucky ones), Vaan found himself transmigrated into the body of an orphan in the world of witches and demons.

However, they didn't always exist.

Demons terrorized the world ever since the Gehenna Realm descended over 300 years ago. but along with them, came mana, giving birth to witches to combat these demons.

Since then, the world of men was dominated by witches, establishing the seven witch kingdoms, which safeguards at the forefront of the demon invasion.

In order to survive in the matriarchal society of the witch kingdoms, Vaan, like all other men who cannot use magic, had to learn how to service the witches to survive.

Nevertheless, it did not come without its own benefits.

Years of research have led the world to the discovery of intimacy between men and women could increase the witches' mana absorption.

But at the same time, men could absorb some of this mana to improve their physique and lifespan.

Thus, since then, an intricate relationship was formed between men and witches in the red-light districts. Love became casual, and dual cultivation is common.

As a prodigy in the art of pleasing women, Vaan lived a smooth two years since his transmigration as an orphan.

However, everything came crashing down in a heartbeat one day when his life was nearly taken, and Lady Eniwse whom he served went berserk.

Even so, that was not the end.

With the awakening of the Witch Hunter System, watch how Vaan takes on the world and becomes the lord of witches.

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Note: Contains lemons.
Hunting witches does not necessarily imply killing witches if you know what I mean ( ͡° ͜ʖ ͡°)

(Warning: Harem, if you don’t like it, please refrain! Boldly breaking taboo ethical norms, not letting go of any beautiful women encountered!) A young nobleman with a delicate constitution, pure and kind, has always been protected by everyone. However, after two months of military camp life, he began to change for the worse. With unbeatable power in his hands, he became lawless, targeting countless beautiful women in the city. In his eyes, every beautiful woman is like a delicate flower. He wants to gather these tender flowers around him, then extend his strong wings to shield them from any harm...

Lin Luoran is a 27-year-old girl from a rural family. She doesn’t have a college degree, let alone any money.

After cheated by her boyfriend, Lin Luoran accidently finds a mysterious space in her heirloom. At first, she only tries to use the magical spring water in that space to grow medicines like ginseng to help out her family. However, Lin Luoran never thought that she would become the last female cultivator in the world.

The family of cultivators have not been seen on earth for thousands of years. Lin Luoran strives to cultivate herself in the metropolis, to complete her first-ever journey to immortality.

As for love… What will happen to Lin Luoran, a girl that is so different? Let’s open the book and find out.

- Description from Novelupdates