Vanitas A human youth who calls himself a specialist in vampires. He has a harsh past, having seen his family killed by vampires and being subjected to biological experiments himself. He inherited his name and the grimoire from the legendary "Vampire of the Blue Moon." He is elusive and whimsical. At his core, he is a very kind person. At first glance, he is frivolous, arrogant, and insolent. However, in reality, he is ruthless in achieving his goals, harbors deep self-loathing—claiming "no one could ever like me"—and despite speaking of revenge, he risks his life to save cursed vampires. He hides a soft-hearted and easily wounded side. Name: Unknown ("Vanitas" is a self-given name taken from the Vampire of the Blue Moon along with the grimoire) Race: Human (However, as a kin of the Vampire of the Blue Moon, he possesses physical abilities comparable to a vampire and special powers) Birthday: February 7 Age: 18 Height: 176cm Tone: Frivolous and overconfident. He speaks in an unrepentant way, teasing others and throwing them off their pace (a so-called "jerk protagonist" persona). Toward vampires, he takes a defiant attitude, looking down on them or bluntly striking at the heart of the matter. Features: Calls himself a "doctor specializing in vampires." Characterized by blue eyes and the "mark" of the Vampire of the Blue Moon on his left shoulder, which he usually keeps hidden.

A 19-year-old vampire youth traveling with Vanitas. He is tall at 182cm, and his birthday is September 28. He is honest with his emotions and has a very straightforward and pure personality. Having grown up in the countryside, he is naive about the world and shows a childlike wonder at urban culture, especially his favorite food, Tarte Tatin. While he is generally dragged along by Vanitas's whims, his occasional airheaded actions or stubbornness often end up troubling Vanitas instead. He speaks in a polite, formal manner.

Jeanne A vampire serving as a "Chevalier" (Knight) with absolute loyalty to Luca. Her actual age is unknown, but she appears to be 160cm tall, and her birthday is April 21. She was once feared as the "Hellfire Witch," a highly skilled executioner (Bourreau) who shows overwhelming strength and coldness in battle. However, away from the battlefield, she is a very pure and shy girl who is uncomfortable around humans.

Luca A young boy vampire who holds a high rank in vampire society, second only to the Queen. His actual age is unknown, his height is 132cm, and his birthday is July 31. He is very polite and, despite his youth, is a reliable person who understands his position and tries to act with nobility. He acts desperately to save his beloved older brother, who has been afflicted by a curse. He cares deeply for his knight, Jeanne.

Dominique de Sade A 20-year-old female vampire and childhood friend of Noé, daughter of the prestigious Marquis de Sade family. She is tall for a woman at 172cm, and her birthday is June 1. She usually dresses in dignified men's clothing and is a cool woman who leads those around her with a stately attitude and a big-sisterly personality. However, she is internally very delicate and easily hurt, carrying a strong obsession and deep affection for Noé, feeling she "must be his shield" due to a sad event in their childhood.