Oscar Claudel is a supporting character in Croisée in a Foreign Labyrinth - The Animation. He is an older French craftsman and the owner of the metalworking shop called Enseignes du Roy, located in the Galerie du Roy shopping arcade in nineteenth-century Paris. The shop is a family establishment that he operates alongside his grandson, Claude Claudel. Oscar serves as the head of the Claudel household and has spent much of his life devoted to his trade, and he is described as an experienced craftsman with a deep familiarity with his work.

Oscar's background includes considerable travel. Before the story begins, he journeys to Japan in order to deliver orders for a wealthy family, and it is during this trip that he encounters the young Japanese girl Yune. He brings her back with him to Paris, and upon his return he announces that Yune will live and work with the family going forward. This decision acts as the catalyst for the entire series, since Claude is initially opposed to the arrangement but gradually comes to accept Yune as part of the household. Oscar has effectively sponsored Yune's stay in France, giving her a home and a role in the shop, and his openness to a foreign culture stands in contrast to his grandson's more reserved and cautious outlook.

As a person, Oscar comes across as a worldly and good-natured figure. His willingness to travel across the world and to welcome a stranger from another country into his home suggests a natural curiosity and a trusting, generous disposition. He is comfortable in his role as an elder and places responsibility on Claude, expecting him to help manage the shop and look after Yune in his absence. He does not dominate the story, but his presence is felt throughout, as the arrangement he initiated shapes the daily life and relationships of the central characters.

In terms of his role in the story, Oscar functions as the bridge that connects the two main worlds of the series. His travels and his decision to bring Yune to Paris allow the series to explore the meeting of Japanese and French culture at the end of the nineteenth century. He is also the figure who entrusts the family legacy of metalworking to Claude, making him an important link between the older generation and the younger one. His motivations appear rooted in goodwill; he seems genuinely interested in giving Yune an opportunity and in broadening the horizons of his own household, even if his choices initially cause friction.

Oscar's key relationships are with his grandson Claude and with Yune. With Claude, he shares both family ties and a professional bond, and he relies on Claude to keep the shop running. With Yune, he acts as a kind of guardian figure, having personally brought her to France and arranged for her to be cared for. Their connection is one of mutual respect and fondness, and although Oscar is not the central focus of the anime, his bond with Yune is the reason she is able to find a new life in Paris.

As for development, Oscar is largely a steady and unchanged presence throughout the series. The emotional growth in the story belongs mainly to Claude and Yune, while Oscar remains the benevolent figure who set events in motion. He does not undergo a major personal transformation, but his influence is essential to the gradual understanding that develops between the members of the household.

Regarding notable abilities, Oscar is a skilled metalworker and an experienced craftsman who runs a respected ironwork shop. His profession requires precision, patience, and a strong knowledge of materials, and the shop's reputation rests on the quality of the work produced there. He is also a seasoned traveler, having made lengthy journeys across the world at a time when such travel was difficult, which demonstrates both resourcefulness and a willingness to embrace the unfamiliar. These qualities, combined with his warm and open nature, define him as a memorable supporting figure in the series.