MTL - Yin Yang Eye GunGun’s Marriage Contract - Chapter 3 The lord will feed the first meal

This story is about a rookie researcher, who was forcefully dragged away from his restful life, compelled into facing various killers and zombies, always having to risk his life at the brink of death, and finally becoming an advanced researcher that is acclaimed by all. And throughout his adventure, he met an alluring(?) killing machine, who he started to have fantasies on after they had an accidental kiss…

Xiao Yan: Did I fall for him? But he’s a man!

Maya: Who knows…. maybe it’s the other way round?

- Description from Novelupdates

The eldest son of the assassin aristocrat Tuatha Dé.

The skill, experience, knowledge of the previous life, magic, all of which grows his power as an assassin.

Excellent assassins pass through. He was usually admired as the ideal lord, and behind it wielded a blade as an assassin aristocrat.

This is a world where humans, demons and mysterious beasts coexist.

Humans cultivate mysterious qi. Demons cultivate corporeal bodies. Mysterious beasts cultivate soul perception.

A legend says that in the middle of an endless rainforest, there are extremely powerful existences; they are called demon kings.

Some demon kings have a tyrannical corporeal body, some are experts in illusions.
Some demon kings are proficient in magic, some can even move mountains.
Some demon kings are able to sense things thousands of miles away.

These demon kings rarely appear in the human world. Even if they emerge in the human world, they would reincarnate in human form; assimilating with mankind while seeking to breakthrough realms…

- Description from Novelupdates

Jiang Shang travels through the Zongman world, but the first world is Fuyuki City?

Joan of Arc, who was not supposed to be alive, came to her door and begged him to participate in the Holy Grail War?

I thought it was the beginning of hell.

At the critical moment, the system awakens!

Just make choices, or rewrite the plot, to get amazing rewards!

“Ally with Joan, get: Top Heroic Spirit Template!”

“Choose to save Matou Sakura, get: Imaginary Space!”

“Summon a mad-ranked servant, get: the holy gun of the end!”

The Holy Grail War begins!

Facing the arrogant King of Heroes, Jiang Shang showed his magic whip under the dull gaze of all the heroes!

“Arrogant tyrants should be beaten constantly.”

“I won’t stop until you admit your mistake.”

- Description from novelbuddy