Isekai Demon Lord Summoning ~ The Case Where an Old Man Was Summoned as a Demon Lord Instead of a Hero!

“Please, Demon Lord, save us!” In typical isekai summoning stories, it’s often a hero that gets summoned. But this time, the ones around aren’t humans—they’re all demons!? What are they going to do by summoning an old man like me? And to make things worse, the one who being summoned isn’t a demon but just an ordinary human! Once they find out, they start saying things like “Kill him!” or “Use him as a test subject!” as they please. Even an old man gets mad sometimes, you jerks (an old-fashioned expression)! I had no intention of helping the demons at all, but after various circumstances, I end up standing with the demons in a war against the humans…