Kautsu is the main protagonist of the series, a young man who arrives in a fantasy town seeking employment. He is hired to work at a peculiar armor shop, a decision that places him at the center of the story's daily events.

Raised in the countryside, Kautsu possesses a demeanor that is often described as stuffy or straight-laced, which stands in stark contrast to the nature of the shop he works for. His rural upbringing has resulted in two notable traits: he is terrible with women, often becoming flustered or uncomfortable around them, and he cannot use magic. This lack of magical ability is a recurring characteristic that distinguishes him in a world of sword and sorcery.

His primary motivation appears to be managing the shop's finances and enduring his unconventional workplace, as the store specializes in selling revealing and erotic armor for female adventurers, which, while having high stats, has caused the business's financial situation to worsen. Compared to the shop's eccentric owner and peculiar customers, Kautsu often serves as the relatively normal straight man, reacting to the absurd situations that unfold around him.

Within the story, his key relationships involve his co-workers, including the shopkeeper Narden, who is passionately dedicated to selling erotic equipment, and the cheerful storefront girl Lilietta. He also regularly interacts with customers like the fiery swordswoman Frealica, who enjoys teasing him for his prudish reactions. In terms of development, Kautsu's role remains consistent as the focal point through which the audience experiences the shop's daily chaos; his growth is primarily shown through his continued attempts to navigate a job for which his unassuming and naive personality is ill-suited. His notable abilities are largely absent, with his defining trait being his lack of magical skill, forcing him to rely on his ordinary, grounded perspective in a fantastic setting.