Sebastian and Ciel are the two main characters of the popular manga series "Black Butler" written and illustrated by Yana Tobosco. The series is published by Yen Press in North America and has been adapted into an animated series and a live-action film that was released in Japan on Jan. 18, 2014.
The story's plot revolves around 12-year-old Ciel Phantomhive and his ever-present butler, Sebastian. Ciel is an earl in Victorian-era London who comes into his own after his parents are murdered. Ciel is subsequently kidnapped and tortured for a period of time by a mysterious group. When he is finally released and returns to London, he is accompanied by Sebastian, a demon masquerading as Ciel's butler.
As the series unfolds, it is revealed that Ciel has entered into a contract with Sebastian in order to acquire the demon's services to help the boy extract revenge on those who murdered his parents. Ciel offers Sebastian his soul as payment for his help. In addition to the dynamic relationship between Ciel and Sebastian, the pair are also commissioned by the Queen of England to help investigate a number of supernatural occurrences that plague the English aristocracy. As of Oct. 10, 2014, the series has sold over 18 million copies worldwide.