He yearns to return to the glorious black company wage slavery of Japan.
That's more of a reflection of the author's limit of knowledge on those topics. Can't expect a ass and titties harem writer to understand the nuances of technological advancement.
His parents are dead but his uncle and aunt who raised him are still there. Mc basically just disappeared out of thin air from earth so they'd worried.
the thing that made him happiest back on earth was relaying his day-to-day life to his parents' graves. im pretty sure that's something he doesn't want to stop doing, since he's been writing in his diary even in the other world
