Horizon, Bright Moon, Sabre - Chapter 23 - Mysterious Old Man

Good news: I have transmigrated to Teyvat and become the Heavenly Principle.Bad news: The world of Teyvat doesn’t have much time left.Good news: I have a system that allows me to devour two-dimensional worlds.Noah looked at the countless familiar worlds, tears of sorrow streaming down his face, and announced on the spot:“I will not only be the Heavenly Principle of Teyvat but also the Heavenly Principle of countless worlds.”“So, my rules are the laws.”From then on, one Heavenly Principle and a group of fierce Gods embraced trembling worlds one after another.After devouring the world of Demon Slayer, Teyvat’s lifespan increased by 5,000 years.After devouring the world of Akame ga Kill!, Teyvat’s barriers were strengthened by 100 times.After devouring the world of Inuyasha, Teyvat forms the cycle of reincarnation.…

Let’s fight! Go! Who am I afraid of with a chip that turns into a brain cell? ! Get promoted and get rich! The nest treasures are all mine!

- Description from novelbuddy

Entering the mortal world for a hundred generations, do not compete for the youth of one life, but only for the day and night of a hundred generations.

Seeking immortals in the world of mortals.

My name is Li Qing. I have escaped from the mortal world in the third life, entered the Tao in the ninth life, and become immortal in the hundredth life.

(longevity stream, non-simulator, non-reincarnation rebirth)

(Bai Shi Shou Yuan, One Life Life)

- 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 ͡°)