A-kun (17) no Sensou - I, the Tycoon?

Onodera Goushi is a high school student who goes largely unnoticed by others, feeling as though his absence would have little impact. One day after school, he encounters a life-threatening situation and is rescued by a mysterious girl named Honoka, who transports him to another world. He arrives in the "Demon Nation," a realm inhabited by various non-human beings. There, he meets the Mahou, who surprisingly turns out to be an anime otaku.