Jam Ojisan is the creator and father figure to Anpanman, having brought him to life when a shooting star landed in his oven during baking. This event unintentionally birthed the hero. He possesses extensive knowledge across various fields and demonstrates expertise in both baking and mechanical engineering, inventing specialized machines like the Anpanman Mobile. Physically, he resembles Anpanman but shows age through gray hair, fluffy eyebrows, a mustache, and lighter red tints on his cheeks and nose. He consistently wears a white chef's hat, shirt, pants, and apron, with blueish-gray shoes. His personality reflects kindness, warmth, and a deep commitment to helping others find happiness. Within the narrative, Jam Ojisan nurtures Anpanman as his own child, offering encouragement and guidance. He similarly supports other bread-based heroes like Shokupanman and Currypanman, though Currypanman's origin as his creation varies across media. He cohabits with Batako in a familial bond despite no blood relation, with some sources indicating their acquaintance dates back to her infancy. His pet dog, Cheese, is his constant companion. Jam Ojisan acts as a paternal figure to Melonpanna and shows persistent concern for Rollpanna despite her conflicting blue heart, repeatedly inviting her to join the bakery's inhabitants. He also encourages Creampanda's abilities. A key part of his role involves regularly baking replacement heads for Anpanman when the hero sacrifices portions of his head to feed starving creatures; this act simultaneously restores Anpanman's strength. In the lore of Anpanman's world, Jam Ojisan and Batako are categorized as fairies, as no humans exist in this universe. Early depictions showed him smoking a pipe, a characteristic later discontinued. His name was unspecified in the original 1973 picture book, where he was referred to simply as "uncle" or "old man". His capabilities extend beyond baking to include motorcycle operation and undisclosed skills potentially related to his inventor and researcher roles. He remains central to sustaining Anpanman's heroic actions through both mechanical support and emotional encouragement.