The Sacred Land Is Going Bankrupt, I Invented a Mobile Phone! - Chapter 13: Reputation Explosion!

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 strongest hero of humanity, Kim Sung Bin.

Mechanics fix things.Fighters break ‘em.Those were the two truths Perry lived back on Earth. When he got isekai’d into a young noble with newfound magical powers, he found himself stuck with an awful choice. Try to survive on the Front, the mystical battleground where Hydras and Devils roamed free… Or find another way.So he took an oath. An oath that made him a Magus Dominus. A mage lord. He’d escaped his fate, least for the moment.For most his life, Perry was used to being alone. When he got sucked into Ro'an, he was suddenly thrust into the role of surrogate son to his loyal servant and half-brother to a tempestuous Storm mage. With their help, Perry prepared his best to be lord and protector for his domain. And if he fought a few monsters, and helped a few people along the way, well…Mechanics fix things. And fighters break ‘em.-Progression Fantasy with light LitRPG elements-No romance-Kingdom building and magic progression

Zhou Wenwen, who had traveled to a parallel world because of sudden death, thought that he could only live in such an ordinary life in this life, but the golden finger finally opened. He has a store where he can buy technological items and magic equipment to ensure his survival.

But the threat that followed made him realize that this place is not ordinary, because there are Transformers, Marvel, the Dark Portal from World of Warcraft, etc.

- Description from novelbuddy