The Tale of the Lost World Lost World

"Different worlds; same fate"

Grey's life was considered to be perfect 'til a horrible disaster killed half of the population of the world; including his family and his best friend. Thus, he decided to end his life and jumped on the apex of the bridge. However, outside the vast universe, a world where demons and magical creatures exists summons his wandering soul. Grey Turner was greeted by the previous Demon King and was asked to save his kind in the brink of extinction.
"Help me, wanderer, for I shall grant you a new life and power. Thou shall bestow my pride and honour. Free my people and attain the world's greatest desire;
Peace for humanity and demons"

I do not own the cover of this book (the illustration is from the popular anime called Overlord)