Binchou-tan, the main character in the anime, is a young girl who lives by herself in an old house far from town. As her name suggests, she often wears a piece of charcoal on her head. Each episode depicts a day in the life of Binchou-tan who needs to work in order to buy food and necessities.
She is assumed to be an orphan because she lives by herself, refuses to answer shopkeepers who ask where her mother is and keeps to her habits of greeting and farewelling herself when traveling. She apparently, also possesses the ability to change the size of her body. Normally she is the size of a small child, but in some cases she can shrink herself to for instance fit in a shoe or to ride on the back of a duck.
She also treasures clothing made by her grandmother which becomes a plot point in one episode. Binchou-tan is initially a very lonely person. Her birthday is on May 07.