In 2017, after the Abyssal Legion's invasion ended, a certain mage who had been dragged into the war as cannon fodder vanished into the endless void along with the defeated Abyssal Legion.
Decades later, Earth, having absorbed the benefits of civilization from a fantasy world, has recovered from the war. Countries and factions have all transformed from the invaded into invaders, beginning to project their influence into other fantasy realms. And a certain cannon-fodder mage, who had disappeared into the void, somehow finds his way back to this world.
It's great to get a second life. My goal this time is to save up enough money to retire back on Earth!
And, while I'm at it... become a truly epic mage!