Berg Alphons, a former salaryman reincarnated into a new world, now resides in the capital city of Ostrava. He possesses three unique abilities granted by a goddess: a talent for creation that improves with practice, extensive alchemical knowledge accessible as if flipping through pages in his mind, and a secret, unmentionable skill crucial for his survival. His current livelihood depends on crafting and selling potions, which allows him to afford a modest rented house.
In Chapter 3, Berg visits the slave market, a common practice in this world where human rights are often disregarded. He encounters a severely injured elf, missing limbs, ears, and eyes, a victim of a cruel former master. Despite his initial hesitation, Berg, driven by a desire for research and a sense of pity, purchases the elf for one gold coin, intending to use her for an experiment. He brings her home in a vegetable basket.
Upon arriving home, Berg attempts to administer his potions to the elf, but she cannot ingest them. He resorts to bathing her in potions, which elicits a slight relaxation from her. He views this as the first step in his experiment, believing that if she recovers, his actions will be deemed good, and if she dies, evil, a harsh reality of this world.
Chapters 8 through 10 detail Berg's alchemical process. He can conceptualize potions of varying ranks, from E to S, visualizing them by color. He creates recipes unique to him, which he keeps secret to avoid the fate of a famous alchemist who was killed for mass-producing B-rank potions. Berg limits himself to crafting C-rank potions and above, though he possesses the knowledge for S-rank potions capable of healing severe injuries, but they are prohibitively expensive and dangerous to create. He meticulously crafts a C-rank potion using specific ingredients like Adrel grass, Tornial tree roots, and Ebistria's magic core. The process involves precise timing and careful handling. Berg's income from selling these potions is substantial, allowing him a comfortable life, though he prefers a low-profile approach to earning.
In Chapter 11, Berg observes that the C-rank potions are insufficient for the elf's recovery, only slightly alleviating her pain. He contemplates using his single S-rank potion, stored in a treasure chest for emergencies. The elf's faint groan, interpreted as a cry for life, convinces him to use the potion.
Chapter 12 describes the dramatic effects of the S-rank potion. The elf's limbs regenerate, and her eyes and eardrums heal, though accompanied by significant pain. Berg realizes he needs to provide her with proper clothing and undergarments. He purchases them and returns to find the elf, now a beautiful, golden-haired, blue-eyed elf, significantly recovered. To his relief, she expresses gratitude, not hostility. He learns she can understand human language and is slowly regaining her memories. She reveals she heard him, referring to him as "Berg-sama" and acknowledging him as her savior. Berg helps her dress, noting her delicate skin and the potential for her magic to have also recovered.
In Chapter 13, the elf, named Lena Sale, is still recovering and experiences a fever. Berg prepares a simple meal of seasoned rice, and she tearfully expresses her gratitude, confirming Berg's actions were indeed good. He reflects on his own adaptation to this world and feels a sense of pride.
Chapter 14 details Lena Sale's continued recovery and her growing capabilities. She proves to be an efficient helper in Berg's potion-making business, offering valuable suggestions and improving their meals. Berg notes that his S-rank potion supply is depleted, and he wishes to create more, but the key ingredient, Phoenix tail, is rare. Lena Sale expresses her gratitude for the S-rank potion and offers to procure ingredients herself, but Berg is hesitant due to the dangers involved. He agrees to take her to the city to familiarize her with the surroundings.
Chapters 15 and 16 depict Berg and Lena Sale exploring Ostrava. Berg explains the city's structure, its prosperity, and its underlying social divisions. He introduces Lena Sale to the Merchant Guild, where they meet Mew Linia, a friendly beastkin who handles Berg's potion sales. Lena Sale demonstrates her literacy, impressing Mew. Berg plans to expand his business into creating status-effect potions, which are in high demand. Lena Sale expresses her desire to stay by Berg's side, not wanting to be free or have another master.
Chapters 17 through 20 focus on the deepening relationship between Berg and Lena Sale. They share meals, and Lena Sale expresses her happiness and devotion to Berg. Berg grapples with his own desires, complicated by their master-slave dynamic and his past trauma of panic disorder in his previous life. He confides in Lena Sale about his past, and she reciprocates by sharing her own harrowing experiences of being a slave. Their bond strengthens, leading to an intimate relationship.
Chapters 21 through 26 describe their daily life. Berg continues his potion business, and Lena Sale becomes an indispensable partner, managing household tasks and assisting with his work. Berg plans to create status-effect potions, explaining his strategy of building his brand first. Lena Sale expresses her unwavering loyalty and desire to remain by his side. They visit the Adventurer's Guild to pick up materials for the new potions. Berg realizes he forgot to include a crucial ingredient, the "medicine herb," in his order and decides to gather it himself, despite Lena Sale's insistence on accompanying him for his protection.
