Black Butler II (TV)

The previews and information given before this series aired tricked many fans of its predecessor into believing that the original Kuroshitsuji's main characters, Ciel Phantomhive and Sebastian Michaelis, would not be reappearing at all. In fact, both of them return for a role in the series. This is even reflected in the first episode's opening, which only features the new characters. The opening for the second episode adds Ciel and Sebastian, as well as other supporting characters from the prequel.

The colors of the contracts made between the butlers and young masters could be dependent on the eye color of the butlers. The contract on Alois's tongue is golden, which matches Claude's eye color. The contract on Ciel's eye is purple. Purple is a combination of blue (Ciel's eye color) and red (Sebastian's eye color).

In episode 4, Claude hands a letter to Sebastian to give to Ciel. If looked at closely, one can see that "Phantomhive" was incorrectly spelled "Phantmohive." This actually occurs both times the letter was seen in the episode. Since it happens two times, some people think it was an intentional gag, but it was most likely just an error.