The Case Study of Vanitas

In a steampunk version of late 19th century Paris, humans and vampires have come to coexist relatively peacefully, largely because humans believe they were all wiped out. There are a few cases, however, where a vampire appears to go rogue and prey upon his human neighbors once more. There is only one man who seems to know both the reason and the cure for this madness, a man calling himself a “vampire doctor,” Vanitas. When young vampire Noé comes to Paris at the behest of his master, he comes into contact with Vanitas, who appears to be nothing more than a silly young man. Oh, how appearances can be deceiving… <em class=de-emphasized>(from manga)</em>

Synopsis from Anime News Network