MTL - There is No Bottleneck In My Practice - Chapter 123~ -128 The Puppet Project, Younger Yang Cheng,

Every human has their Personal Jewel of power, when awakened it can either be an Elemental Jewel or Physical Jewel. They circle the right and left wrists like bracelets of power.

Yo, Hi! I’m Frank, I made a deal with a demon to pay me some money for receiving a guest for a few days every week.
I had no idea about what I have done.
On May 1st, Conan ‘the God of Death’ came to my house. I was forced to let him in and we get involved in a criminal case.
On May 8th, Bruce Wayne ‘Batman’ came to me. I was forced to follow him to fight crime.
On May 16th, Hannibal Lecter, The Silence of the Lambs, came to my home. I can only say that I really can’t stand my guests.

- Description from Novelupdates

Lin Yu crossed into the world of the Demon Slayer and started the mode of rewarding hard work.

Each physical training can bring the increase of its own attributes, and there is no limit to the superposition.

The flesh is sanctified, and the power is supreme.

Fallen Ji looked in fear at the tall man in front of him, whose body was covered in shadows. The machete-like Japanese sword behind the man was bigger than her entire body, and her neck was being stabbed to death by a strong arm. ‘s grasp.

“Unarmed… catch a ghost?”

Yi Wozu couldn’t remember how many times his wounds had healed in the fierce battle, and the corners of his bloodshot eyes were fierce and excited.

“A mere human can actually reach this level, are you a monster?

bring it on!

I would like to call you the strongest. ”

Ghost Dance? Wu Miserable: Trembling…

- Description from novelbuddy

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 ͡°)