The protagonist, summoned to the alternate world <Arcadias>, embarked on a journey to defeat the Demon King and return to his original world. But that was long ago. After various circumstances made his return impossible and left him virtually unkillable, he decided, half in despair, to establish his own nation, creating an environment convenient for himself. Now, 400 long years later, the nation he built from scratch has taken deep root in both the human and demon realms, becoming an impregnable state thanks to his power.

Then, one day, a report reached him.

To his surprise, a resident from his original dimension had been summoned — or rather, had 'fallen' — to this world, just like him. Eager for news from home, he decides to embark on a journey, but...

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While this is an 'isekai' story, I believe it offers a slightly different narrative than usual. The protagonist's abilities are fundamentally overpowered, but they are not geared towards combat. I'll state upfront that the strongest character in this work is the (prospective) heroine. Recommended for those who are fine with that.

Updates are irregular and slow.

And this work is definitely story-focused!