The Golden Empire

Kurogane Tatsuya is just an ordinary high school student with a bit of a chuunibyou streak. But one day, he is suddenly transported to another world. Unable to understand the language and possessing no power, Tatsuya is enslaved in this world. However, after managing to escape, he meets a girl called a "demon"—Razwald. Under the girl's care, Tatsuya learns the language, accumulates knowledge, earns a living, moves to the capital, and expands his connections. Gradually, he builds a place for himself in this world. But a terrifying threat looms—the invasion of fanatics is reaching toward the continent where Tatsuya and his companions live. The enemy commands an army of millions of soldiers. Together with his companions—Kafura, the daughter of a great merchant, and Safir, a swordsman—Tatsuya stands up to face the invading army of a million. *This work has been retitled "Golden Empire Kuroy" and published as an e-book.