Kennosuke Tsurugi is a young Japanese boy who becomes a key member of the Dandelion Troupe during their travels across Europe. He is a descendant of samurai, a heritage that shapes his identity and sense of honor. After being orphaned, he left Japan for Europe with the determination to earn money to support himself and his sister, Hanako, who was left behind. His personal dreams are split between two aspirations: to become a skilled samurai like his ancestors, or to become an aviator, a goal inspired by a dreamy inventor he worked for in Japan who wanted to build flying machines.

Kennosuke’s introduction to the Dandelion Troupe is far from graceful. In England, his curiosity gets the better of him when he sneaks into the troupe’s car, causing it to race uncontrollably through London with the young performer Rita trapped inside. Despite the chaos he causes, he is forgiven and subsequently joins the company, finding a new home among the performers. His primary role within the troupe is multifaceted. On stage, he performs dynamic dance and fighting sequences using a bokken, a wooden sword, and occasionally partners with Nadja for her dance acts. Behind the scenes, he serves as the troupe's skilled mechanic, responsible for maintaining and repairing their vehicle, the Happy Carrier Car.

In terms of personality, Kennosuke is portrayed as kind, earnest, and friendly. He is also notably enthusiastic about gadgets and mechanical devices, a trait that aligns with his dream of flight. His most prominent personal storyline involves his feelings for the protagonist, Nadja Applefield. He harbors a clear crush on her, which often manifests as jealousy when she becomes too close to other boys. However, this romantic interest is typically treated as a lighthearted running gag rather than a source of serious drama, and regardless of his feelings, he remains a loyal and supportive best friend to her.

Throughout the series, Kennosuke forms several important bonds. His relationship with Nadja is central, and he often accompanies her on adventures and errands, such as searching for clues about her past or helping other people they meet along the way. He also becomes very close to Rita, the troupe's shy singer. In one notable episode, he and Nadja work together to discover the truth about Rita's past, which helps her overcome a significant personal obstacle. His presence also creates minor rivalries, as he finds himself at odds with Nadja’s other suitors. The character experiences a gradual development as he integrates fully into the European traveling life. While he starts as a somewhat reckless outsider, his skills as a mechanic and a performer make him an indispensable part of the troupe. His understanding of friendship and responsibility deepens through his interactions with the other characters, and he learns to balance his traditional samurai values with the new world he now inhabits. His notable abilities include his prowess with a wooden sword, his athleticism as a dancer and stage fighter, and his practical mechanical know-how.