I only remember it vividly but in that manga, the hero is an android made in the past by the humans to defeat the demons who invaded the human world and the hero doesn't age. So now the world isn't that developed after the invasion of demons. And there is a demon queen and her generals' hero goes to demon world ask for job or to be her general I forgot.
1 Answer
You are looking for Yuusha, Yamemasu
After saving the world, the strongest hero who has no place to go anywhere, Leo. A power that is too strong can not enter the peaceful world …… Such a place of employment where he arrived – the former enemy, the Magus army!
