The story follows Hannah Falset, a young woman with a deep admiration for the legendary adventurer "Princess of the Sword," Rainy. Hannah's village was destroyed by monsters, and she was found and raised by Rainy, an elf who left her adventuring career to care for her. Despite Rainy's kindness and strength, Hannah feels a sense of inadequacy due to their racial and physical differences, believing she can only truly connect with Rainy by becoming an adventurer herself. She extracts a promise from Rainy to travel with her if she becomes an adventurer.
However, Hannah's dream faces a significant obstacle: she possesses absolutely no talent for combat. At the Salt Larch Adventurer Academy, where she has been for two years, her sword level remains at zero. She is mocked by her classmates and given the derogatory nickname "Donketsu Hannah" (Bottom-rank Hannah). Despite her efforts, she fails to improve with swords, spears, axes, or even magic staves.
The academy's director, Bazel Salt Larch, a renowned adventurer known as the "King of Swords," witnesses Hannah being bullied and initially seems to defend her. However, he abruptly expels her, citing the academy's tradition of never having a student fail the adventurer exam. He believes weak individuals like Hannah corrupt the academy by giving others false hope and hindering their efforts. Enraged by his dismissal of her two years of hard work and the implication that her efforts are meaningless, Hannah challenges Bazel to a duel by throwing her glove.
Bazel accepts but assigns his daughter, Cecil Salt Larch, the academy's top student and a formidable swordswoman, to fight Hannah. Cecil, possessing all the talent Hannah lacks, easily defeats her. Devastated and facing expulsion, Hannah recalls Rainy's parting words and her desire to be called "mother." She realizes she must become strong enough to travel to the dangerous "Demon Land" where Rainy resides.
With no other options, Hannah leaves the academy with only 150 Pel and a single bag. She tries to find work at a job placement agency but is rejected due to her lack of skills, as her "Skill Tree" shows no abilities. Desperate and with dwindling funds, she seeks refuge at a half-built cathedral dedicated to Pharma, the Goddess of Cooking. There, she encounters a group of carpenters rebuilding the cathedral after a fire. The foreman, impressed by her willingness to help despite her lack of skills, offers her a job as a laborer.
Working on the construction site, Hannah discovers an unexpected affinity for hammers. While initially drawn to them due to their association with the evil god Doltos, she finds she can use them with surprising ease. Her "Blunt Weapon Level" rapidly increases, and she learns various skills. The carpenters, initially dismissive, come to respect her dedication and unique talent. After a year, the cathedral is nearing completion, and Hannah, now a skilled carpenter with an exceptionally high Blunt Weapon Level, decides to pursue her dream of becoming an adventurer.
The carpenters gift her two custom-made hammers, a small nail hammer and a large two-handed one, and she heads to the Adventurer's Guild. At the guild, she is met with skepticism and ridicule for her choice of weapons. However, when she attempts to register, her extraordinary skill levels and the unusual nature of her "Blunt Weapon" classification cause confusion. She is informed that she must undergo a practical exam, coinciding with the arrival of her former classmates from Salt Larch Adventurer Academy.
