B100X - Auto Dungeon RPG

In the world before the birth of mankind, the heavens were dominated by God and the earth was dominated by demons. The player becomes a "witness" who assists the apostle "Holly" of God, and challenges the seal of the "Eternal Magic Cave", which is a terrifying monster's nest. What is a demon? What is God's true purpose? What is the relationship between the Holly Apostles and humans?