The narrative begins with Shun waking up in a new world, accompanied by Shiro, a white-haired cat beastkin, and Ao, a blue slime. They find themselves on a well-maintained dirt road in a peaceful, rural landscape. Shun, having been a salaryman in his previous life, recalls his death from overwork and a chance encounter with a celestial bus that transported him and the stray kitten he was holding to this new world. He learns from a divine being that he can no longer reincarnate in his original world and is offered a new life in this world, which possesses magic and is less technologically advanced. Shun is granted the skills of Item Box, Appraisal, and World Map, and his companions, Shiro and Ao, are transformed into their current forms and become his familiars. Shun is also de-aged to fourteen and given a more attractive appearance.
The group sets out on the road, with Shun planning to register as an adventurer, take on quests, and travel. He instructs Shiro and Ao to keep their origins a secret. Their journey is initially peaceful, with Shun preparing for a potential night of camping. They encounter a pack of wolves, and Shiro and Ao, despite Shun's caution, impulsively charge into battle. Shun supports them with magic, and they quickly defeat the wolves. They continue their journey, encountering more wild animals, which they defeat, using these encounters as practice for their newfound magical abilities. Shun notes that Shiro and Ao tend to rush into combat, leaving him as the sole rear-guard.
As evening approaches, they set up camp. Shun uses magic to prepare the campsite and cook a meal with ingredients from his Item Box and the recently hunted game. He also uses cleaning magic for their dishes and themselves. Shiro expresses a desire to sleep with Shun, and they settle down for the night, with Ao tasked with keeping watch.
The next morning, they wake up and resume their journey. They continue to encounter and defeat wild animals, which serve as valuable combat and magic practice. Shun observes that Ao, despite being a slime, enjoys charging into battle alongside Shiro. As they approach their destination, the number of people on the road increases, and they are greeted warmly by villagers. Shiro, in particular, charms an older group of women with her enthusiasm for becoming an adventurer.
They arrive at a large, fortified city, the capital of a border count's territory. After receiving guidance from the women they met earlier, they proceed to the Adventurer's Guild. Inside, they are greeted by attractive receptionists. Shun registers himself as a "Magician" and Shiro as a "Magic Fighter." Ao is registered as a familiar, receiving a special potion that causes a mark to appear on his forehead. Shun also accepts an offer for a free beginner's lecture for the next day. He inquires about recommended inns and learns that the "Komadori-tei" is a good option.
Following the receptionists' advice, they head to the material processing area of the guild to sell the wolf carcasses they hunted. They are met by a gruff but fair man who praises their clean kills and the quality of their materials, especially noting the effectiveness of Ao's blood-draining. He contrasts their well-preserved materials with those of a "noble-like adventurer" who brought in damaged wolf parts, highlighting the importance of proper handling for higher valuations. With the sale complete, they decide to head to the recommended inn.
