In 'Black Butler', there are many interesting arcs. For example, the Circus Arc. Ciel and Sebastian investigate a circus troupe that seems to be involved in some dark secrets. The story shows the contrast between the bright and cheerful appearance of the circus and the underlying evil. It also delves into the complex relationship between Ciel and Sebastian, as Sebastian is always on the verge of devouring Ciel's soul once he has completed his revenge mission.
Another aspect of 'Black Butler' is its portrayal of the Victorian society. The elaborate costumes, strict social hierarchies, and the prevalence of the occult in the background. Ciel, as a young Earl, has to maintain his family's status and reputation while secretly plotting his revenge. The anime and manga are filled with beautiful art that brings this world to life, from the grandeur of the Phantomhive manor to the seedy underbelly of London's streets.
The 'Black Butler' story mainly focuses on Ciel Phantomhive and his demon butler Sebastian. Ciel, a young noble, has a tragic past. His family was brutally murdered, and he made a contract with Sebastian to seek revenge. Sebastian, with his extraordinary abilities, helps Ciel navigate the dangerous world of the Victorian era nobility, dealing with various mysteries, murders, and political intrigues along the way.