Ciel Phantomhive, a 12-year-old English aristocrat of the 19th century, is the heir to a prosperous toy and confectionery company. He lives in a manor with only his servants for company, including his faithful butler named Sebastian. This latter is actually a demon with whom the child has made a pact. Thus, the boy offered his soul in exchange for his protection until he achieves a mysterious vengeance. Meanwhile, Ciel and his butler solve various criminal cases in an effort to eradicate crime from their country.