The story follows Dias, a man who has lived his life by his deceased parents' dying wishes: to do work that helps others and to become a man who can protect the weak. For twenty years, he fought in a brutal war that began when he was fifteen, eventually becoming a celebrated hero at the age of thirty-five. Despite his accomplishments, Dias is humble and bewildered by the praise, especially when the King grants him a territory.
Upon arriving at his new domain, Netzlooss, Dias is met with contempt by the officials. He discovers his territory is nothing but an endless, barren grassland with no inhabitants, homes, or resources. Left alone with only his battle axe and worn armor, Dias faces the immediate challenge of survival. He finds a clear stream, a source of water, but struggles to find food or shelter. He realizes the grass is inedible and useless, leaving him with a sense of despair. He resolves to survive for two more days before seeking out a village to find work that aligns with his parents' wishes.
The next morning, Dias is abruptly woken by a woman with striking red makeup, a strange patterned cloth, and a pair of glowing blue horns on her forehead. This woman, Arner, interrogates him aggressively, demanding to know why he is in her territory and what his intentions are. Dias, though initially confused by her questions about "blue" and "red," eventually explains his situation and his desire to help others and protect the weak. Arner, seemingly satisfied by his honest answers, reveals that she and her people, the Oni, are not his subjects but his enemies, having long been in conflict with his kingdom. Despite this revelation, Dias declares his loyalty to her and her people, which causes Arner's horns to glow intensely. Arner then drags Dias to her village.
The Oni village is a collection of yurt-like structures. Arner introduces Dias to their leader, Moll, an elderly Oni with blue horns. Moll explains that the Oni have lived in hiding for fifty years, using concealment magic to remain undetected by the kingdom after a devastating war. She reveals that Dias's blue-glowing horns indicate he is someone who brings them fortune, unlike the previous, unpleasant lord of the territory who recently died. Moll offers Dias a yurt, livestock (Mea), and provisions in exchange for his silence about their village and his promise to gather actual villagers and become a proper lord. Arner is assigned as Dias's caretaker.
Dias begins his new life, learning from Arner about the Mea, a crucial livestock whose wool is used for high-quality fabric. He also learns about the importance of hygiene and the construction of yurts. His first task is to hunt for resources to trade for necessities like a well and latrine. Arner provides him with "Matabi" powder, a scent that attracts beasts. Dias, eager to prove himself, uses the powder and hunts a large herd of "Black Gee" (bull-like beasts). This display of "manliness" (a concept the Oni value highly, equating it to capability and worth) greatly impresses Arner and Moll, changing their demeanor towards him.
Arner, now visibly smitten with Dias, offers to accompany him on hunts. They venture north to a monster-infested area. Arner uses her magic to locate a large monster, an "Earth Dragon," which she identifies as dangerous. Despite Arner's fear, Dias decides to confront it, while Arner agrees to use her concealment magic for their escape if needed. The chapters end as Dias charges towards the Earth Dragon, ready to fight.