Batako-san, also known as Butterko-san, assists Uncle Jam at his bakery with a bright, optimistic, and hardworking spirit. She busies herself baking, cleaning, handling laundry, and delivering goods. Her crucial duties include stitching and mending the capes of Anpanman and fellow heroes, as damaged capes strip them of flight. Occasionally, she displays forgetfulness.

Early concept art proposed her discovery as an infant in the woods by a young Anpanman, but this was abandoned. Instead, she is older than Anpanman, witnessed his birth in the series' first episode, and helped raise him alongside Uncle Jam, forging a familial bond that casts her as a maternal figure.

She shares an unspecified family-like connection with Uncle Jam and nurtures a close relationship with Anpanman, frequently replacing his compromised head and repairing his cape. She named the dog Cheese, advocated for his adoption, and interprets his barks. Her interactions with supporting heroes like Shokupanman and Currypanman remain positive yet less emphasized than those with central characters. A past long-distance relationship with Omusubiman exists but goes unelaborated in later stories.

Physically, she stands taller than Uncle Jam, featuring rosy cheeks, black eyes, a small round nose, and spiky black hair—shorter in later series iterations. Her typical attire includes blue overalls over a white vest and a chef's hat that hides her bangs, revealing a bowl-cut hairstyle when removed. Despite her human-like appearance, few humans inhabit her world.

Across media like the 1992 anthology "Anpanman to Yukai na Nakama-tachi," her role persists: supporting bakery operations and aiding heroes. Available materials omit specific character development or expanded backstory beyond these functions. Her abilities encompass precise throwing—notably delivering Anpanman's replacement heads mid-battle—and multilingual communication with non-human characters like Cheese.