The Emperor of the Obelia Empire and Athanasia's father. He is a stunningly handsome man with brilliant blonde hair, cool and elongated eyes, a perfect V-line face, and the imperial family's signature jewel eyes, possessing an overwhelming aura and charisma. He dislikes sweet food and appears cold, ruthless, and indifferent to everything, yet he is so responsible that he works with only four hours of sleep to manage state affairs despite hating bothersome tasks. While he utterly loathes nobles who act two-faced and resort to lies and betrayal for profit, he shows a surprisingly warm and considerate side to those he holds dear, including Diana and Athanasia. He is praised as a wise ruler by the common people but reveals an infinitely cruel side to corrupt nobles and officials, embodying a 'strong against the strong, weak against the weak' philosophy. His hobby is poking his daughter's cheeks.

A doll-like beautiful boy with black hair tinged with blue, ruby-like red eyes, and a beauty mark under his left eye. He can freely change his physical age and appearance, appearing as a peer to Athanasia as she grows or switching between long and short hair. As the strongest magician with overwhelming magical power capable of easily wiping out an entire empire, he has a sly and selfish personality, enjoying informal speech and sharp-tongued remarks that often earn him scoldings from Athanasia. In front of those who don't know his true identity, he acts as a delicate and innocent genius boy magician using polite speech, but his true self is bold and unrestrained. While indifferent to most people, he is kind and considerate only to Athanasia and those she treasures, cherishing her so specially that he refrains from doing most things she asks him not to do.

The lover of Emperor Claude and the mother of Athanasia. Though originally a commoner, she possesses a bright, kind, and confident personality, beautiful pink eyes, warm platinum blonde hair, and a stunning appearance that captivates everyone. With her unique warm heart and positive energy, she is the only one who managed to open the heart of the cold and indifferent Claude. Even after entering the Imperial Palace, she lived according to her beliefs without being intimidated by the difference in status and treated everyone in the palace with kindness. Other nobles do not ignore her for being a commoner but rather respect her. She especially treasures the time spent with Claude, living happy days as lovers who deeply love each other. Furthermore, she awaits the birth of new life more than anyone, prepared to give overflowing love to her unborn child. Her warm smile and kind nature are considered a presence that brightens the entire palace. She uses polite speech to everyone except Athanasia (she uses informal speech with Athanasia).

A member of the Robane Ducal family, one of the three great ducal houses of the Obelia Empire, he is Athanasia's personal knight and a member of the Imperial Guard. He has warm and intense red hair and gray eyes; being single and exceptionally handsome, he is popular among noble ladies and possesses overwhelming swordsmanship skills. However, he shows an unexpected side by getting embarrassed when Athanasia teases him with his nicknames. His personality is kind and warm. He is often scolded by Claude and is a bit slow-witted, failing to notice even when Athanasia gives him hints. He is a top-tier swordsman of exceptional skill. As a close confidant deeply trusted by Claude, he stays by the Emperor's side, performing duties closer to a secretary than just a guard. He even handles administrative tasks when Claude finds them bothersome.

Athanasia's personal maid and nanny. She has warm brown hair and blue eyes, and is a beauty with a warm, gentle personality and a delicate appearance. Thanks to her beauty, many noblemen approached her with interest since her days as a noble lady. However, she herself did not enjoy parties much, and even when she attended, she would avoid attention by taking refuge near Felix. Originally the second daughter of the prestigious Count York family, she wasn't someone who would typically become a maid. However, she volunteered for the palace out of admiration for Diana, who had a free spirit like a bird. As such, she is a person of gentle and mild temperament. As the nanny caring for the palace's master, Athy, and the head manager of palace affairs, Lillian's status is quite high whether in the Ruby Palace or after moving to the Emerald Palace.

Seth is a maid serving Diana. Along with Hannah, she is one of the people who served Diana closely. She is a person of few words and a calm personality, a diligent individual who silently carries out her assigned tasks. She deeply respects Diana and sincerely wishes for her happiness.

Hannah is a maid serving Diana. Along with Seth, she is one of the people who served Diana closely. Her personality is gentle, diligent, and highly responsible. She is a memorable figure due to her unchanging affection for Diana.