A comic adaptation is serialized in COMIC Unicorn.

One day, Wataru unexpectedly discovers a gate that allows him to travel back and forth between another world and Japan.

Beyond the gate lay a world reminiscent of a fantasy realm.

Upon seeing a town with many underdeveloped aspects of civilization, Wataru recognizes the potential to make a fortune.

He brings "spices," "coffee," "hygiene products," and other goods into the other world, joins the Merchant's Guild, and accumulates vast wealth.

Having become immensely wealthy in the other world, Wataru examines the goods sold there and suddenly has a realization.

"Wait, isn't the other world actually superior when it comes to *this*?"

Wataru brings a wound medicine that instantly heals injuries—the so-called "potion"—back to Earth, making another fortune in Japan.

Moreover, Wataru, who also buys a beautiful slave, eventually expands his activities beyond Japan, achieving great success across the entire Earth.

Please note that this work is also pre-published on Kakuyomu.