Harry Potter: Dimensional Wizard - Chapter 644: Avengers' Training: Captain America

Lu Zhou wakes up to become the world’s most powerful and oldest villainous Patriarch, and finds that he has nine notorious disciples who are full of evil. His eldest disciple is the leader of the Nether Sect with thousands of minions, and his second disciple—Sword Devil—always slaughters others at the slightest disagreement…

One week. If you survive, you choose a Cosmic Power... you survive. Jace isn’t one to give up. Not when his sister dies. Not when he loses his legs. And definitely not when The Cosmic System takes over Earth. With nothing more than his street smarts, the clothes on his back, and a river otter companion; he must survive a planet full of vicious predators that see him as an easy meal. If he can survive? He gets to choose a Cosmic Power and a Class. A path to ascension. A way to bring his sister back.

It’s a world of men.

It’s a mystical tribe.

Liang Yue crossed over as the son of the chieftain.

The whole tribe is concerned about Liang Yue’s marriage.

Every races in the whole tribe want to have baby with Liang Yue~

- 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 ͡°)