D.Gray-man, Kuroshitsuji Recommendations
Both series take place in a victorian era and have occult themes, such as demons. The characters and plot are very different, but are both appealing and interesting. They are both unique series filled with loveable characters.
While there are not many similarities in the characters, the feel of both anime series is similar. Both are dark and deal with exceptionally young antagonists forced into adult roles. Both series deal with demons and humans and have complex relationships between the dark and the light sides. And both antagonists are fighting a history much longer than their own lifetime.
Having watched Kuroshitsuji right after finishing D.Gray-Man, a few "common terms" were noticed, though in very different contexts.
"Akuma" -- Demon. The enemies in D.Gray-Man, and one of the protagonists of Kuroshitsuji.
"Hakushaku" -- Earl. Referring to both Ciel in Kuroshitsuji and the Millenium Earl in DGM.
Also, both have young protagonists with a "cursed" eye, and many characters. Also Allen and Ciel both are half in the "white" and "black" worlds.
Both anime series involves action, comedy, demons, ans supernatural powers. While Kuroshitsuji is about unraveling a mystery behind the horrendous tragedies about the main character's past, D. Gray-man is about seeking to stop to the ultimate plot that could lead to the destruction of the world. Both of the hero and heroines gained help from their comrades, in Kuroshitsuji the other servants and in D. Gray-man, the exorcists.
Both take place in a Victorian era. They also have very similar animation styles if that's what catches your eye.
They both contain demons and other supernatural elements.
These shows both contain very serious dark moments lightened by jokes and silly facial animations.
Kuroshitsuji has a much more extreme side to the light hearted content.
Main characters have a strong past that make them the character they are in the show.
D.Gray-man obviously has the better character depth because it has more episodes and you get to know and love them as the show progresses.
If you love the era of D.Gray-man while sticking with the supernatural themes, Black Butler is