Fourth grader Kasumi Haruno arrives in Kasumi Town to see off her parents, both zoologists, as they leave for research in Africa. While they are away she will stay in the Kasumi family's large mansion, which stands in the middle of town with forest all around it. Something strange hangs over the Kasumi Forest, and inside the mansion the appliances can talk. The Kasumi family turn out to be youkai known as Henamon. To earn her place in the house, Kasumi takes on the cooking, cleaning and laundry, and she begins a new life among these mysterious companions in a slice-of-life fantasy.