Monster Factory - Chapter 669: Built here.

I, Seiren Shikino grew up in an orphanage. On the day of my high school graduation, I somehow got transported to another world, and turned into a girl as well. ……Eh, this isn’t my original world and gender, right!? It seems that I’m now Seiren, the daughter of a noble from another world. This is a light hearted story about family and romance.

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 a famous plastic surgeon in the 21st century, both at home and abroad. But one day, she transmigrated to become a young lady in the Prime Minister’s Mansion and got bullied. The concubine hung her up and beat her, forcing her to marry a fifty years old general as his second wife! But unexpectedly, she received an imperial edict and was asked to marry the emperor’s fifth son – the Evil King.

Who was the Evil King? A gunpowder explosion destroyed his appearance and one of his eyes. After waking up, Evil King’s temperament changed drastically. The handsome young man became a bloodthirsty and cruel tyrannical king. This was not even the most frightening thing. It was said that the Evil King had four wives, but none of them had lived over a month!

Last night, the Evil King’s fourth wife died. Today, she was tied up and sent to his mansion …

- Description from Novelupdates

The MC entered the body of the An family eldest son, An Ziran, an arrogant 16 years old boy who weighed 78 kg (~171-172 lbs), who only knew how to eat, play and sleep. Seeing his current body, An Ziran decided his first priority was to LOSE WEIGHT!