A cold-hearted prosecutor who judges criminals even by fabricating evidence, Honjo Weisaku. One day, he lost his life with his wife and daughter in an unexpected accident and fell into hell. There was a “Millennium Festival” held by demons. The demon Bune sets his sights on Wei Shuo as a “devil’s agent” who participates in it and offers him a contract. If you participate in the Millennium Festival and get the legendary Solomon’s ring, any wish will come true. Not only you can revive your family… When. After signing the contract, Wei Shuo throws himself into the Millennium Festival as Bune’s agent and wields the sword of judgment against the demons. Will he be able to get Solomon’s ring? A man who wields a fierce skill as a prosecutor judges the devil, the ultimate dark fantasy.