Laius Perseus leads the Perseus community, inherited from his father. After his father's death, he implemented significant changes conflicting with the community's established traditions.

He sports dual-colored hair in an unusual pattern: golden blond from top right to bottom left and dark brown from top left to bottom right. His attire typically consists of a snakeskin jacket featuring brown shoulders, a red long-sleeved shirt bearing the Perseus symbol, black pants, and brown boots. A distinctive black ribbon choker with a Medusa head pendant functions as the summoning device for the Celestial Star Spirit Algol. Laius defines himself through hedonism, prioritizing money, alcohol, and women. He displays consistent arrogance and disrespect toward authority figures like Shiroyasha, frequently abandoning responsibilities. This arrogance stems from reliance on powerful Gifts: Algol, the Harpe, the Boots of Hermes, and the Hades Helmet. He initially viewed the No Name community with disdain due to their lack of status, refusing duel engagements.

Three years before the main events, he acquired the vampire Leticia Draculea at a slave auction but later grew disinterested due to her unfriendly demeanor. He contemplated selling her externally, fantasizing about potential exploitative uses despite her childlike appearance not appealing to him personally. His interactions reveal consistent traits: overt lust toward Black Rabbit led him to attempt blackmailing her into lifelong servitude by exploiting her compassion and loyalty to secure Leticia’s release. He harbored deep animosity toward Kudou Asuka after she used her Gift on him, reacting with lethal intent. He showed immediate contempt for Sakamaki Izayoi, transforming into profound fear after Izayoi obliterated Algol during their duel.

During negotiations at Shiroyasha’s shop concerning Leticia’s fate, he antagonized Shiroyasha and the No Name representatives. He refused Black Rabbit’s initial duel challenge, citing lack of evidence, but later accepted when she presented requisite treasures. In the Gift Game <<FAIRYTALE in PERSEUS>>, he awaited challengers in the Colosseum and summoned Algol against Izayoi and Jin Russel. His confidence evaporated as Izayoi systematically destroyed Algol and countered every attack. Facing defeat, he realized Izayoi’s true objective was seizing Perseus’s name and flag, which would reduce his community to No Name status. A final desperate attack failed, compelling him to accept the loss.

This defeat stripped Perseus of most power and prestige, forcing significant changes. Laius developed a heightened sense of preservation for his community. While retaining elements of arrogance, he adopted a more humble approach, later forming an alliance with the No Names and the Will-O-Wisp community. His teacher in item creation, Jack-O-Lantern, maintained a contentious relationship, frequently ejecting him from workplaces. Willa the Ignis Fatuus of Will-O-Wisp addressed him familiarly as "Lui Lui," indicating reasonably amicable ties. By volume six, he shifted focus toward craftsmanship, seen wearing blacksmith attire: a dark apron with the Perseus symbol, gloves, and a satchel holding tools. He demonstrated expertise in Gift creation and modification, repairing and enhancing Asuka’s Gift "Deen" and crafting others like "Amalthea" and "Aegis," reaching divine-tier proficiency. He participated in reviving Amalthea alongside Jack, with no further connection noted between them.