MTL - Three Kingdoms - Chapter 2740 Uneasy

Kiyoshiro Takeda lived a life without purpose, drifting through his days with no direction. But one fateful moment changes everything. Now, he finds himself in a world unlike any he has ever known, given a role he never asked for. A new life, an unknown destiny, and a looming catastrophe that only he can prevent. But can someone who failed in his old life truly become the last hope?

In the end-French era, after countless calamities, the era of cultivation is coming to an end. The last combination of air transportation and evolution has evolved into the treasure board, which was obtained by the last practitioner in the end-French era, which opened up a legend of wandering heavens.

- Description from Uukanshu

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.