Olivier serves as a Paladin of the Third Unit within the Chasseurs, the holy order hunting vampires, bearing the title "Olivier of the Obsidian" linked to his rank's black stone. He is 27 years old, born November 3. His physical appearance features a slim build, pale skin, a thin angular face, narrow upturned eyes with long lashes, defined eyebrows, and long dark hair typically secured in a loose hip-length ponytail that often obscures one eye. He wears the standard Chasseur uniform: black trousers, a cassock, a white harness, a purple belt, dark leather boots, and a dark purple rosary. He is aware of his own acknowledged attractiveness. His personality blends a generally laid-back attitude with intense frustration, particularly directed at his close associate Roland Fortis. Though he often prefers others to make decisions and expresses laziness over troublesome situations, he demonstrates strong loyalty and takes his Paladin duties seriously. He recommended Roland for the position of Emerald Paladin ten years prior to curb his irresponsibility, but remains exasperated by Roland's persistent flippancy and disregard for protocol. Olivier possesses significant intuition, enabling him to predict Roland's behavior patterns, like his tendency to get lost, and locate him efficiently. He maintains a polite and reserved demeanor with strangers but reveals a more judgmental and high-strung side with those he knows well, especially Roland. Olivier also smokes cigarettes and holds the belief that his father will ultimately select his marriage partner, leading him to avoid deep romantic attachments. In combat, Olivier wields his unique blade, Hauteclaire (also known as "Noble Black"), which resembles a non-rotating chainsaw. His fighting style is notably brutal and reckless, frequently resulting in the weapon becoming blunted or damaged. He commands respect among the Chasseurs for his strength and combat prowess. His relationships are complex. His bond with Roland Fortis is central, marked by deep trust alongside constant friction due to their opposing approaches to duty and Roland's shifting perspective on vampires. Olivier actively discourages Roland's newfound belief in human-vampire coexistence, warning it could endanger Roland's position and family. He demonstrates unwavering loyalty, staying at Roland's bedside after a near-fatal injury and vowing to leave the Chasseurs if Roland did not recover. Olivier shares a history with Astolfo Granatum, viewing him somewhat as a troublesome younger brother and showing understanding toward Astolfo's family struggles. He intervened physically to stop Gano's cruel remarks following a tragedy in Astolfo's family. Olivier's interactions extend beyond the Chasseurs; he once encountered Vanitas in a café, listening to Vanitas's romantic concerns and offering advice. Key plot moments include his early appearance investigating disturbances caused by Roland, Vanitas, and Noé in the catacombs. He later confronts Roland about his changed worldview regarding vampires, explicitly cautioning him about the potential repercussions. During the events in Gévaudan, Olivier articulates a pragmatic view on hatred, stating it can sustain individuals and should not be taken away from those who rely on it for survival. His involvement often centers on managing Roland's actions, protecting allies, and fulfilling his role within the Chasseur hierarchy.