Protected by a great wall, the Holy Kingdom of Roble enjoyed years of peace. But with the sudden appearance of the Demon King Jaldabaoth and his army of malevolent demigods, peace and tranquility are shattered. Remedios, Grand Master of the Paladins, and High Priestess Kelart gather their forces to strike back. But alone, they are no match for the overwhelming power of Yaldabaoth. As the Holy Kingdom teeters on the brink of collapse, Remedios, along with her order and her follower Neia, sets out in search of help. They finally find it in the sorcerer kingdom of Ainz Ooal Gown, a strange nation ruled by undead, who are actually despised by the humans of the Holy Kingdom. Can they win the battle against the Demon King together?