The Heroine is My Stepsister, and I'm her Final Boss - Chapter 10: "Tea and Trust."

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 ͡°)

Working hard and living frugally, Wen Qian accidentally obtained Spatial abilities, followed by dreams about natural disasters. So instead of buying an apartment, she stocked up on supplies, changing from a city office worker into a countryside food blogger. Then, Wen Qian noticed that reports of disasters around the world were on the rise…

On a harsh rainy day, a high school student without any particular special skills, Usato Ken, got dragged into another world summoning with two others; a good-looking guy and a beautiful girl, both of whom he strangely started getting along with just today. As an especially talentless individual that didn’t stand out, he thought that the others would treat him like he was useless. However, they were unexpectedly kind.———“Maybe things will be fine?”Usato who found hope in another world thought that, but the reality was different. He had a certain magic talent hidden within him and he was forced to fall into hell under the name of “training”.

“Honey, be good…Give me your phone…”

“No, no!” The internet-addict girl clutched onto her phone, determined not to give him.

The handsome and noble man slightly sighed. He lowered his body to hug the girl.

“You’re not listening again, hm?” She immediately handed her phone over cowardly as he said so in a clear and distinct voice.

He was the eminent and noble Master Li, a powerful figure in the business world.

She was just from a normal family that suffered from her stepmother’s schemes, a pitiful girl.

An accident made him appear in her world.

Since then, everyone in S City knew that Master Li had a treasure and cherished her dearly. He feared that she might be wronged in the tiniest bit. He will personally tutor her in her studies, personally be her training partner in video games, and even reserve the movie theaters for her movies.

- Description from Novelupdates