User blog comment:B214/Question and Answers 6/@comment-9595671-20160714212150/@comment-9595671-20160715023725

True, the biggest difference Highschool DxD has is rather than Satan be "the Devil" and the people of Hell be Demons, they're all just Devils (which I think is a great idea) and Satan's name is used as the opposite to God, it must make it more flexible for the title Satan to be inherited.

That makes Gods' death a secret to all 3 sides because Devils are linked to Christianity and even if not sided with him, God's death could still indirectly affect Devils as a whole via how Christianity itself would be affected.