Beloukas is a merchant operating officially as a monster seller and unofficially as a slave trader in the kingdom of Melromarc, his family being a long line of slave traders with a global reach. He is more often known by his profession than his personal name. Short in stature, he carries a consistently creepy demeanor. His attire is that of a traditional circus ringmaster: a full tuxedo, a long top hat, and a red bow tie fastened with a small diamond brooch. Glasses with a chain, white alchemist gloves, and a small, old-fashioned handlebar mustache complete his look. An ever-present, somewhat sinister grin is a frequent feature on his face, an appearance that mirrors the circus-like atmosphere of his slave tent. He maintains unwavering courtesy and professionalism in all business dealings, speaking politely to clients and offering honest assessments of his merchandise at what are considered reasonable prices. He readily attempts to upsell additional monsters or services for his own profit. He treats his slaves as valuable commodities and generally avoids abuse, as mistreatment would lower their value, setting him apart from slave traders who employ physical punishment. He holds a strong, mutually beneficial business relationship with Naofumi Iwatani, whom he considers a top client, but expresses a distinct dislike for dealing with individuals like Motoyasu Kitamura, whom he finds unpredictable, intimidating, and lacking in business sense. Beloukas provides significant assistance to Naofumi, supplying him with slaves and monsters. He sold Naofumi his first slave, Raphtalia, and the egg that hatched into his second companion, Filo, and also performs the rituals for applying slave and monster seals. This association increases Beloukas's recognition within the underworld. It was later revealed he was initially contacted by one of the Queen's Shadows to sell a slave to Naofumi at a reasonable price without arousing suspicion, though the specific slave was not predetermined. Within the spin-off series *The Reprise of the Spear Hero*, set in a separate timeline, his interactions with Motoyasu are detailed. During an initial time loop, Motoyasu purchases a filolial egg that hatches into a filolial named Kuro. Motoyasu later returns to buy more filolials, actions which terrify Beloukas due to Motoyasu's erratic behavior and growing reputation. In a subsequent loop, after Motoyasu receives a large monetary reward, he returns to purchase Beloukas's entire stock of filolials. Though frightened, Beloukas is impressed by the sum spent and decides to temporarily close his shop afterward to avoid suspicion for aiding the Spear Hero. A piece of trivia notes that Beloukas's character design closely resembles the Millennium Earl from the series *D.Gray-Man*, an observation made by Naofumi in the web novel.