Vanitas

Vanitas is an average human being who inherited his name and the Book of Vanitas from the infamous vampire. He seems to often take nothing seriously and almost always has a broad grin on his face. He acts more on emotions than thought most of the time since his plans are normally reckless. Also carries a mischievous air around him. When he was just a child, his parents were killed by a vampire. He was saved by the chasseurs and taken in. They trained him to become a chasseur but somewhere along the line, Vanitas caught Doctor Moreau's eye and became his research subject. According to Moreau, Vanitas went through multiple experiments that nearly killed him, and yet he never cried nor complained. The experiments continued until he and "no. 71" were rescued from Moreau's lab by Vanitas of the Blue Moon. Unlike no. 71, Vanitas hated Vanitas of the Blue Moon. The events that occurred afterwards are unknown, but Vanitas acquired the Book of Vanitas at some point. Since receiving the Book of Vanitas, Vanitas has dedicated his life to curing Curse-Bearing Vampires and considers himself a doctor of sorts as a result; using the power of the Book of Vanitas to restore a Curse-Bearer's true name.