Set in a gothic, alternate-19th-century Paris, The Case Study of Vanitas follows Vanitas, a human physician who wields the enigmatic Book of Vanitas to cure vampires afflicted by a mysterious curse. He teams up with Noé Archiviste, a calm but enigmatic vampire, as they travel through the vampire underworld to diagnose cases, uncover conspiracies, and reveal the true purpose of the book.

Set in a gothic, alternate-19th-century Paris, The Case Study of Vanitas follows Vanitas, a human physician who wields the enigmatic Book of Vanitas to cure vampires afflicted by a mysterious curse. He teams up with Noé Archiviste, a calm but enigmatic vampire, as they travel through the vampire underworld to diagnose cases, uncover conspiracies, and reveal the true purpose of the book.