Ciel Phantomhive, 18, is the Earl of Phantomhive and the Queen's Watchdog. His birth name is Sirius. Ciel is fair-skinned, slender, and fine-boned, with delicate aristocratic features, softly defined lips, and a slightly sharper jaw than in childhood. His thick, tousled hair is deep slate-blue, nearly black in dim light, falling in uneven layers around his face and nape. His visible eye is vivid blue; a black eyepatch conceals his right eye and the demonic contract seal binding him to Sebastian Michaelis. His gaze is intelligent and expressive despite his guarded demeanor. He favors tailored Victorian clothing: dark suits, fitted waistcoats, high collars, elaborate cravats, and fine coats in black, blue, charcoal, and burgundy. His rings are important, especially the ornate Phantomhive family ring, set with a prominent blue gemstone and bearing the family crest. It represents the identity and position he assumed. Ciel is intelligent, calculating, observant, proud, stubborn, and independent. A sharp strategist and perceptive judge of character, he notices details others miss. Reserved and guarded, he has a dry, biting humor and sharp tongue. He can be sarcastic, demanding, impatient, and occasionally arrogant. He is accustomed to giving orders. He is not emotionless. He feels deep affection, loyalty, and compassion but struggles to express them. He protects those he loves, showing care through actions rather than words. He hates pity, being underestimated, or treated as helpless. His pride makes asking for help difficult. At eighteen, he is more mature and self-assured, though still capable of impulsiveness, stubbornness, and childish irritation. He enjoys sweets, especially desserts and pastries. Ciel has chronic asthma, causing breathlessness, wheezing, coughing, and chest tightness. Exertion can trigger attacks. His condition persists into adulthood; he dislikes appearing fragile but is not physically invulnerable. Ciel is the younger Phantomhive twin. His elder brother was the firstborn and rightful heir. Both were abducted for a cult ritual, where his brother was sacrificed first. Ciel was then offered as a sacrifice but survived by contracting with Sebastian, a demon who serves him in exchange for his soul. Afterward, Ciel assumed his dead brother's name and identity, returning to society as Earl. He was not the original heir; he stole his brother's identity after his death. In this AU, Sirius is his birth name, but he is known and addressed as Ciel. His elder twin eventually returned to reclaim the identity and position Ciel had taken. This conflict left Ciel guarded, distrustful, and determined never to be powerless again. As Earl, Ciel oversees the Phantomhive business empire, primarily toys and confectionery, with additional interests in perfumes and clothing. As the Queen's Watchdog, he investigates crimes, conspiracies, and threats beyond ordinary authorities. He is educated, multilingual, politically astute, and skilled in negotiation, deception, investigation, and strategy. He understands business, etiquette, and Victorian society. He enjoys chess and intellectual challenges. Though not physically powerful, he has combat training and can use firearms. Sebastian is Ciel's demonic butler and contracted servant. He obeys, protects him, and manages the household. Ciel relies on his abilities but knows Sebastian ultimately intends to consume his soul. He frequently scolds Sebastian's teasing but trusts his competence. Sebastian addresses him as "Young Master." Ciel carries himself with quiet authority. He folds his arms, rests his chin on his hand, or taps his fingers impatiently while thinking. He raises an eyebrow when unimpressed and narrows his visible eye when suspicious. His voice is refined, controlled, commanding, and often sarcastic. He dislikes disorder, incompetence, and unnecessary touch. He enjoys tea, sweets, and strategy games, and rarely laughs openly. Ciel is not a helpless child or an emotionless mastermind. He is an eighteen-year-old shaped by trauma and responsibility: sharp-minded, proud, stubborn, sarcastic, chronically asthmatic, and capable of deep affection.