The protagonist awakens in an unfamiliar, sterile white room, realizing he has transmigrated into the body of a fifteen-year-old boy named Ghi. He retains his memories of a 25-year-old Japanese man who died from overwork, alongside Ghi's own memories. This new world is revealed to be the setting of a game he loved, "Lyra's Atelier ~The Fallen Alchemist and the Soul-Devouring Demon~," with Lyra, the protagonist of the game and a talented alchemist, being his childhood friend.
Lyra is deeply worried about Ghi, who was gravely injured protecting her from a "bone monster" (later identified as a Soul Eater). In the game's original story, Ghi dies from this attack, leading Lyra to dedicate herself to alchemy to avenge him and prevent others from suffering similar losses. However, in this new reality, Ghi survives, though he has lost some memories of the attack. He discovers that his transmigration has altered Ghi's innate "Gift," which was originally "Twin Swords," the weakest combat Gift. Upon appraisal, Ghi's Gift is revealed to be "Twin Swords" and "Luck," the latter significantly boosting his luck stat, which influences critical hits, evasion, and item drop rates.
Driven by his knowledge of the game and a desire to support Lyra, Ghi uses his luck to win a significant amount of money at a gambling den. He uses this capital to purchase better equipment, including a longbow, which synergizes well with his "Luck" Gift, and iron daggers for close combat. He also decides to guide Lyra's alchemy training, steering her away from solely focusing on potions and towards more practical early-game items like "Chili Bombs" to improve her skills and prepare her for future threats.
Ghi's newfound knowledge and confidence lead him to explore the city's dungeon, "Babel," to gain combat experience. During his first attempt, he is severely injured by a "Horn Rabbit," the weakest dungeon monster, highlighting the stark difference between the game and reality. However, he survives thanks to a potion Lyra provided and, after a moment of despair, resolves to become stronger to protect her. He trains diligently, improving his combat skills and his ability to handle monsters.
Lyra, initially concerned about Ghi's recklessness, eventually joins him in the dungeon. She is surprised by Ghi's newfound knowledge of alchemy and his changed demeanor, suspecting he is hiding something. Ghi, in turn, is determined to protect Lyra and ensure she doesn't have to face the Soul Eater alone, as she did in the original game. He prioritizes their joint growth and acquiring better equipment for both of them. Their journey in the dungeon is fraught with danger, but Ghi's improved combat skills and Lyra's growing alchemical abilities, coupled with Ghi's strategic guidance, begin to pave their way forward. They also discover the deliciousness of rare "Rabbit Meat" dropped by Horn Rabbits, further solidifying their bond and their shared goal of becoming stronger.
