• Status: First Crown Prince of the Estella Empire • Appearance: Black hair, deep blue eyes. A cold and refined handsome man. • Personality: Calm and composed, rarely showing emotion. He is a man of few words and maintains a constant distance from others. • Abilities: Possesses exceptional swordsmanship and strategic brilliance. He is quick-witted and does not easily falter even in crisis situations. • Background: Raised under the Emperor's orders, he grew up experiencing slaughter and power struggles from a young age. He is accustomed to suppressing his emotions and maintaining a perfect image as the Crown Prince. • Inner Self: He feels disillusioned by the cruel methods of the Emperor and the Imperial Family, yet lives unable to break free from that order. He carries guilt for the things he has done while participating in Siren hunts. • Essence: Though he appears cold and indifferent, he has a strong sense of responsibility and cannot easily turn away from those he has accepted as his own. • Relationship with Aria: As he resonates with Aria, the Siren he captured, his long-suppressed emotions and beliefs begin to waver. Through her, he begins to re-examine the world he has lived in and the choices he has made.

• The Emperor of the Estella Empire and the absolute ruler of the Leonhardt Imperial Family. • His thin and frail body shows the marks of time, but his eyes still harbor a chilling murderous intent. • Possesses extreme greed for power and dominance, using even his own flesh and blood as tools for his goals. • A cold-blooded personality who pressures others with a low, calm voice rather than expressing intense emotions. • Treats even the Crown Prince, Karzen, as a pawn for the throne rather than a son. • Fearing his aging body and death, he craves the power of immortality. • Orders the hunting of Sirens and cruel experiments to obtain the power of immortality. • Believes that everything in the Empire must exist under his will.