Kyuuketsuhime Miyu (TV), Jigoku Shoujo Futakomori Recommendations
The second season of Jigoku Shoujo retains the same dark and moody elements of the original JG even as it explores the interaction between Ai and those who seek her services. This forging of bonds between doomed supernatural females and humans is also very present in the latter episodes of Vampire Princess Miyu. Jigoku Shoujo Futamori reveals a deeper kinship between Ai and Miyu, firmly establishing them as kindred spirits.
There's a single girl, who must perform her duties, who's been around for quit a long time, with a couple of loyal assitants following her around. Horror +2.
The atmosphere in both these animes feels somewhat the same, the case by case problem solving also feels very similar together with the dark setting of the whole anime.