MTL - Billion Technology Crystal System - Chapter 753 : Crisis appears! Be sure!

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 ͡°)

She was the eldest daughter of a famous doctor in Beijing. She was the “Cold Hell King” who was feared by everyone in Beijing. In her previous life, she was used by a scumbag man. She caused him, his family to be ruined, and he died in the basement. In her second life, she stepped on a scumbag man, a scumbag woman, and her three brothers pampered her to the heavens! The three young masters of the Jiang family were scrambling to be the first to do so. “Shui Su is my younger sister, I'll pamper her!” A certain young master Fu in Beijing coldly raised the chin of the woman in his arms with jealousy. “Tell me, who are you?” Ye Shui Su’s eyes rippled slightly. “Linnan, I'm your person.” How could he not believe such provocative words? Fu Linnan’s icy hand moved to the woman’s slender waist. “You can’t just say whether you’re one of my people or not.” [Rebirth + Counterattack + Team Pet + socketed + 1v1 + Female Lead Snatch] [Reborn + Counterattack + Team Pet + 1v1 + Female Lead Snatch]

An Individual from Earth finds themselves in the Shinobi World, equipped with a Scientific System. From that moment, he delved into scientific research far ahead of its time.

On her wedding day, she was humiliated; her status as the legitimate wife was instantly changed into that of a concubine.