The story begins in the ruins of the magic-less city of Varia, once a center of magical civilization. The protagonist, Alan, is a young treasure hunter who makes a living by excavating magical artifacts from ancient ruins. He is pursued by enforcement officers but manages to escape. Alan is frustrated by the lack of valuable finds in Varia, as the ruins have been thoroughly plundered. He is particularly interested in relics related to Gray Fuller, a legendary sorceress known as the "Immortal Silver Moon," who is said to have saved the world during the magical era.
While searching, Alan stumbles upon a staff that resembles a deer's antlers. He initially dismisses it as a replica of Gray Fuller's legendary "World Tree Staff," as such replicas are common. However, upon touching it, a voice calls his name, and he is enveloped in a blinding white light. When his vision clears, Alan finds himself in a bustling, vibrant city, vastly different from the desolate ruins he left behind. He realizes he has been transported to the past, a time when magic still existed, evidenced by flying carts and impossibly tall structures like the Varia Magic Academy.
Alan's primary goal is to sell the staff, which he believes is genuine and incredibly valuable. However, his attempts to sell it to various shops are met with dismissal; they all declare it to be just a wooden branch. Desperate, Alan decides to seek out Gray Fuller herself at the Magic Academy, hoping she will recognize the staff's true worth.
At the academy, Alan encounters a young, gray-haired girl named Gray Fuller, who works as a school janitor. This Gray is a far cry from the legendary hero Alan imagined. She is boastful and clearly not the brilliant student described in historical records. Alan learns that the "Gray Fuller" celebrated in history is actually a different person, a talented student named Faria Esbel, who possesses silver hair and eyes and is the true genius of the academy. The janitor Gray had fabricated her achievements in letters to her hometown to avoid shame.
Alan, realizing the janitor Gray is not the hero he sought, tries to leave. However, the janitor Gray, desperate to maintain her lie, clings to him. During their argument, a colossal, headless black giant emerges from the ground, attacking the city. While most people flee towards the academy for safety, Alan, recalling tales of Faria's heroism, decides to flee in the opposite direction, believing it to be a safer strategy. The janitor Gray, initially hesitant, eventually follows him.
The giant's attacks prove devastating. The academy's defenses, though impressive, are overwhelmed by the giant's regenerative abilities and a black mist that drains magic. Alan, immune to the mist due to his lack of magic, realizes the janitor Gray's earlier boast about her "World Tree Staff" might be her only chance. He forces the staff upon her, urging her to use it against the giant. Despite her initial incompetence, the janitor Gray, spurred by Alan's taunts and a desire to prove herself, manages to channel a powerful attack through the staff, momentarily incapacitating the giant. This act, however, exhausts her, and she is caught by the giant's mist. Alan, witnessing this, is forced to carry her and flee, realizing the legend of Gray Fuller might be a distorted truth, with Faria being the true hero. The narrative ends with Alan and the janitor Gray on the run from the giant, with the fate of the city and their own lives uncertain.
