King of Underworld - Chapter 85: The Goddess of Forgetfulness, Lethe (2)

Being able to learn any skill immediately, and just by raising its proficiency, stand at the summit.

He is the World Chef Association Honorary Chairman, having the title of the World Chef God.

He is the greatest composer, pianist, and conductor after Beethoven and Mozart.

He also has the title of Underground Racing King, Fist King, Gambling King, Giant of the Stock Exchange Market, Arm of the Industries and King of the Skies.

He who has a miraculous learning ability and can stand at the apex of all things if he so wishes for it, the Omni Genius.

- 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.

[Simulation] + [Isekai] + [Goblin] + [Harem]After a long sleep, I awakened in a new life—as a goblin. Weak and insignificant, I found myself reborn as the lowest creature in a world filled with hostility and danger. But from the shadows of this cruel world, a silent rise begins...