Mikhaïl, also known by the pet name Misha, is a boy who possesses the second copy of the Book of Vanitas. He was born to a prostitute mother who abused him and forced him to dress as a girl to assist in her work. After a vampire killed his mother, Mikhaïl was taken in by the church but was soon abducted by Doctor Moreau and became experiment number 71 in a series of cruel attempts to create artificial vampires. During this time, he met Vanitas, who was experiment number 69, and the two formed a close bond, with Vanitas often volunteering to take the experiments in Mikhaïl's place. Mikhaïl received transfusions of the Blue Moon Vampire's blood and was eventually rescued from the laboratory alongside Vanitas by the Blue Moon Vampire himself. After their rescue, the three lived together as a family, with Mikhaïl calling the Blue Moon Vampire father and Vanitas big brother, though they share no blood relation. His memory of the Blue Moon Vampire's death is incomplete, leaving him with only the image of Vanitas holding the dying figure.

On the surface, Mikhaïl appears bright and gentle, but his personality is deeply distorted by his traumatic past. He is unable to tolerate pain and craves the warmth of family, driven by a powerful sense of loneliness. He is highly perceptive and a skilled manipulator, capable of orchestrating complex schemes to achieve his goals. His primary motivation is to restore the family he lost, seeking to reunite with Vanitas and the Blue Moon Vampire and live together once more. To this end, he orchestrates a confrontation at an amusement park, using Dominique de Sade as a tool to lure Noé into a trap. He forces Noé to drink his blood to show him his memories, intending to later have Noé drink Vanitas's blood to uncover the truth about the Blue Moon Vampire's fate.

In the story, Mikhaïl serves as a key adversary. He wields the second Book of Vanitas, which allows him to manipulate and implant suggestions in vampires, such as ordering Dominique to jump from a great height if she does not comply. Because of the experiments and blood transfusions, he has become a pseudo-vampire and a follower of the Blue Moon. His relationship with Vanitas is deeply conflicted: he loves his brother but also resents him for the perceived betrayal of killing their father. His connection to Naenia, a mysterious black figure, suggests he may have become a bearer of a curse in pursuit of his goal to bring back the Blue Moon Vampire. Over the course of the narrative, Mikhaïl's innocent childhood gives way to a fixation on recovering what he has lost, driving him to increasingly extreme actions.