I Sell Hellish Goods in the Human World

Caesar, who had just traveled to another world, became the slave of the devil. He must pay one million gold coins to regain his freedom. But in a strange world, how easy is it for him, a stranger, to make money? Fortunately, the devil also gave him a torn book called "The Secret Recipe of Evil". Relying on this torn book, he continued to create hellish specialties in the human world, beat up the local products in the human world, and gradually established his own business empire. Years later, Caesar still wanted to say those words. "Demon of the Trench!!!" [It is recommended to use the perspective of the male protagonist of galgame]