Batako-san assists Uncle Jam in the bakery, known for her dedication, hard work, and occasional forgetfulness. Her name means "Butter Girl." She witnessed Anpanman's birth and, alongside Uncle Jam, helped raise him as part of their family, establishing her as a core maternal figure.

Her duties extend beyond baking to laundry, cleaning, deliveries, and sewing. She repairs torn hero capes to restore flight ability and crafts items like dresses. A key recurring task involves replacing Anpanman's damaged head; she physically throws him a new one during battles or recovery.

She possesses rosy cheeks, black eyes, a small round nose, and spiky black hair that shortened over time. Her standard outfit is blue overalls over a white vest and a chef's hat covering her bangs; removing the hat reveals a bowl cut.

Her personality is consistently kind, caring, optimistic, and polite, rarely arguing. She maintains a busy presence, often seen performing tasks supporting the bakery or heroes. Relationships are central: she shares a motherly bond with Anpanman, named and advocated keeping the dog Cheese, frequently translates his barks, and delivers bread with him. Her relationship with Uncle Jam is familial and loyal. She once had a long-distance relationship with Omusubiman. She maintains generally positive interactions with other heroes like Currypanman and Shokupanman.

Early concept art depicted her found as a baby in the woods by a young Anpanman, but this was discarded for a version where she is older than Anpanman. Her human-like appearance exists within a world otherwise devoid of humans.