The Sword and Heir of Shadows - Chapter 59: Her Trembling Hand.

Wen Zhixing has transmigrated into the world of cultivation and has been unexpectedly abducted to the Wondrous Palace, where is full of infamous female cultivators. However, with his Immortality System, Wen Zhixing discovers that he could see their “Fortune Fragments” and take advantage of these Fragments by consuming his lifespan.[ Acquire the constitution: Revival of the Withered Tree.][Revival of the Withered Tree: Blazing Gold Quality. Can rejuvenate a withered body. Each time the body enters a withered state, it will undergo nirvana. After nine nirvanas, it will shed its mortal form.]...

Before Li Daniu had time to be excited about being a prince who was about to ascend the throne, he learned that his country was about to be submerged by sea water.

“Can I wear it back?”

- Description from novelbuddy

“Future Occupation…Demon King.”

Sai Akuto enters Constant Magic Academy to be useful to society and to become a top-ranked national magician. However, a horrible prediction is made on his first day. Thanks to this prediction, the class representative girl hates him, a girl with a mysterious power embraces him, a female artificial human is sent by the empire to observe him, and his school life is otherwise thrown into chaos…

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 ͡°)