Sixty years ago, a being known as the Demon King arrived on the continent of Arvium. Death did not stop him — he kept returning. When even the animals fell under his thrall, desperate scholars found a solution: seal the Demon's soul inside a human body. Without his influence, the demonic plague fractured and faded. These human vessels came to be known as Vassals. But the solution was always fragile. The flesh could only contain the Demon for so long before he broke free again. Today, Arvium seems at peace. The current Vassal, Lady Faratras Hoikade, has held the Demon King sealed for nearly 21 years — longer than anyone before her. The people have grown comfortable, even hopeful that He might finally be sealed for good. Appearances can be deceiving.