Demon King Saves the World

A guy is summoned as a new Demon King by the almost extinct Hades Kingdom in a world where the Gods are tyrannical and want to invade Arcadia where the Human and Demonic Kingdoms reside and devour its core to strengthen themselves.

Can he recover his dying Kingdom and save it from the people who want to end it?

Can he unite the Humans and Demons to face against the Gods or will he be the only one standing in a pile of ashes?