DxD: System of the Harem King - Chapter 144: Miura Corp. and the Sanda-kai

Long Fei, a cross-timer and doujin, is an otaku who traveled to another world. In the original world, he was an otaku fan of Gundam and military science fiction.

He died in an accident and was reincarnated into another world. The Gundam works he had read before his death and the techniques in various military novels could be brought to another world.

How would he use the Gundam that Long Fei created? What waves can be caused in this different world?

Feng Ruqing was a spoiled princess with a hideous countenance in Liu Yun Kingdom. She used to ride roughshod over anyone who stood in her way, backed by her father the emperor who loved her with all his heart.

Not only did she force the chancellor’s son to marry her by breaking the existing loving couple up, but her mother-in-law had also passed out from rage because of her. In the end, she took her own life after the heartbreak and humiliation of being dumped.

When she opened her eyes again, she was no longer the bratty princess who was a good-for-nothing.

* * *

Rumor has it that spirit beasts have become servants in princess’ manor and the princess is devouring precious spirit herb dishes every day.

Rumor has it that the chancellor’s son who pleaded for reconciliation after divorcing the princess was thrown out of the princess’s manor.

Rumor has it that some good-looking young masters went to the princess’s manor in hope of being her servants were nearly killed by the state preceptor.

Rumor has it that the charming state preceptor was looking for the princess eagerly as he wanted to hold her responsible for sleeping with him.

- Description from webnovel

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 ͡°)

[You have been slain by an Evil God. Time Reversal initiated.][Save file loaded successfully. Beginning Fifth Playthrough.]In 2030, a game burst onto the scene.And you had already been reborn for the fifth time.Only you knew that in three years, the game would merge with reality.Humans and races from other worldlines would invade Earth through the game.And not long after that, even more unknown horrors would descend upon every timeline![Ding! Congratulations, player registration successful. Please draw your Talent.][Ding! Detected that the player has used a redemption code.][Ding! Redemption code successfully applied. Congratulations! You have obtained the unique Talent: Millionfold Boost!][Talent Description: Millionfold Boost — When selling an item, you may choose to receive a millionfold boost in either quantity or quality!]As expected, the redemption code you had painstakingly gathered during your first four playthroughs was worth it![Detected: Player has sold a Common-grade Bow. Player has chosen Quality Boost.][Ding! Millionfold Boost activated. Congratulations! You have obtained the Legendary-grade equipment: Moon Reaper!][Detected: Player has sold a D-rank Skill Book: Blink. Player has chosen Quality Boost.][Ding! Millionfold Boost activated. Congratulations! You have obtained the SSS-rank Skill Book: God Speed!][Detected: Player has sold a God-grade Pet: Ancient Dragon Egg. Player has chosen Quantity Boost.][Ding! Millionfold Boost activated. Congratulations! You have obtained 1,000,000 God-grade Ancient Dragon Eggs!]Beautiful!You bastards, get ready to face the strongest ancient dragon legion in history!