One Planet for Everyone! Building Science and Technology Civilization at the Beginning - Chapter 11: Win by Quantity! Madly rising planet area!

He was the continent’s strongest and most revered alchemist, Ye Zifeng. He was under one person and above millions. However, due to an unpredictable event, he had died. After his rebirth, he had become the supertrash of the Ye family and suffered disgrace. To make matters worse, he had an argument with his fiancé that led to the break off of his engagement. In this second life, he will work to change his own destiny. He vows to return to the peak of the world, trample on those who laughed at him and rewrite his legacy!

- 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 ͡°)

Princess Anastasia of Orsenia is regarded as the kingdom’s treasure. However, she carries a heavy secret— she is diagnosed with an incurable illness. She is fated to die before she turns 18.

For years, her parents desperately searched for a cure but to no avail. That is, until a mysterious letter arrives, claiming that the only way Anastasia can escape her cruel fate is to send her to a monster:

King Caspain, the ruler of Sorvando, a vampire kingdom.

The letter prophesizes that Anastasia will live, only if she makes that bloodthirsty King fall in love with her. However, Anastasia knows it’s nearly an impossible task. Sorvando is filled with dangers. And she is only but a weak human.

Yet, her will to live won over her fear. No matter how cruel the king may be, Anastasia will still try to win his heart.

Now, if only she can keep her own heart from falling for him as well.

***

[Excerpt]

“Cas-pian…”

And he looked back to see that she was biting her lower lip as though she greatly enjoyed that kiss.

He smirked again and whispered in his deeply seductive voice, “I like my name even more ever since I started hearing it from your beautiful lips. And I like it even further when you say it in that hushed tone.”

Anastasia had no idea what Caspian was hinting at yet.

So he dropped some more hints, “Wife, weren’t you asking me what the first night meant? Let me show you.”

The legendary mana finally reached planet Earth, causing all living things to officially enter the path of evolution.