MTL - Little Mermaid Dressed As a Scientist - Chapter 3

The tomatoes and potatoes are piled up in the warehouse, the dead horses are squeezing the milk, the vampires are carrying the watermelons, the succubuses are picking the eggplants, and the Lich King is quietly licking the ice cream…

The people who died in the crown pointed to the tribes:
Let the dead be born, and let the dead die!

(This book is based on the dungeon and the Warriors, Warcraft, heroes invincible, riding and cutting, and another million finished “Wasteland Ranch” character guarantee)

- Description from Uukanshu translation

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.

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

The planet was invaded by the Tates, and suffered from the devastation of the last ages. In the crisis of survival, some humans awakened powers, and they realised that those mutant beasts could cooperate with their own consciousness and increase their fighting power to two times more.

This kind of animal was called Warpet. Shu Xiaohui was somewhat different from others. When the Tates invaded, he became a hamster and silently felt the presense of another powerful person.

Chen Chengduo watched his companions slowly find their warpet, and wondered where his one was until one day he saw Shu Xiaohui with his mouth full of melon seeds in the corner of the wall…

Others were warpet, his was only just a pet right…

Hamster: You… You don’t look at my small size. I have lucky BUFF!

- Description from Novelupdates