Based on available information, Emil is the younger son of the British journalist Michael Booth. He is four years old and travels to Japan with his father, mother Lissen, and six-year-old brother Ansger for a one-hundred-day culinary journey.

In the story, Emil serves as one of the two young children experiencing Japanese culture and cuisine for the first time. His primary role is to react to the new and often unfamiliar foods alongside his older brother, providing a family-centered perspective on the adventure. He is present for many of the family’s dining experiences, and his reactions often highlight the comedic elements of cultural exploration.

His notable trait is a tendency to mumble when speaking, which can make his dialogue difficult to understand. In one documented episode, both Emil and Ansger inadvertently consume a large amount of wasabi and are overwhelmed by its spiciness, leading to a negative reaction when their father later brings them to a wasabi-producing region without telling them the destination first. Beyond this, there is no detailed information about his personality, motivations, character development, or specific abilities. Information on his individual relationships, aside from his family dynamic as the younger sibling, is also not available.