8 years ago, the last time in history humanity itself wasn't near extinction. Magic users led by the human nations summon heroes, known only as the "Divine Four", to fend off the demonic hordes from hell led by the Devils' Legion. These four individuals supposedly from the heavens itself were to bring peace to all the lands, however the humans misunderstood one severe factor, the heavens wanted their world too. In what was known as the final age of mankind, an unexpected event occurred- The devils started to actively seek conflict against the angels. No advances have been made by any armies since then. The last of the humans are confined to a single fortress, known as The Mighty Kriegstein Castle.
No-one can be trusted, not even God himself.