Elf Tensei Kara no Cheat Kenkoku-ki - Chapter 9Book 2: -3: Negotiations

Ham Dani, a normal student whose hobbies were to read novels.

One day she woke up and find out that the girl next-door is as beautiful as a web novel protagonist.

And in school, there was the introduction of ‘The Four Heavenly Kings’.

The world changed into a web novel just over night, and Ham Dani’s role is heroine’s childhood friend 1!

“I just want to live normally, but why is everyone doing this to me!”

Due to a strong fate ‘The Four Heavenly Kings’ and the heroine entwines Dani’s everyday life.

And the results are?

The celestial celestial beings who lived for more than 100,000 years were born and reborn in a small monk in a human world.
His motto: “It’s not as good as a medicinal medicine for ten years of hard work.” “Even if you practice a copper-iron bone, it’s not enough for my soldier’s attack.”

- Description from Novelupdates

The world was once at war with 10 alternate worlds. This was known as the Concept War and our world won 60 years ago. All of this was concealed so no normal people are aware of this fact in the current time.

After the death of his grandfather, the high-school student Sayama Mikoto is suddenly summoned by the giant corporation IAI. He learns this world is headed for destruction due to the acceleration of the Minus Concepts. To prevent this, negotiations must be undertaken with the survivors of the other parallel worlds so their 10 concepts can be released.

And so Sayama is caught up in the final battle to clean up after the Concept War which left behind so much enmity.

Everyone says he is an iceberg, but only Maya Spencer knows he is a volcano, and moreover, a volcano that is passionately unlimited for her, an indulgently pampering volcano.