Hiling is the Queen of the Bosse Kingdom, having married King Bosse as his second wife, which made her the stepmother of the protagonist, Bojji, and the biological mother of Daida. Before becoming queen, she led a life as a traveling monastic or cleric, a background that is the source of her powerful restorative magic. She is a woman of average height with a thin build, long blond hair that she often wears in a style making it appear chin-length, striking blue eyes, and a prominent nose, typically adorned in a regal red dress and golden crown.

Her personality is a complex blend of external sternness and deep-seated care. Initially appearing as a haughty and cold queen, she is a character defined by her contradictions. She has a brusque, sometimes socially awkward, and domineering demeanor that often comes across as harsh, yet underneath this facade, she cares deeply for the people around her, particularly her two sons. She is fiercely determined, self-assured, and extremely protective, to the point of being overbearing. Her love for her children is genuine and profound, but she often fails to express it appropriately, leading to misunderstandings. Despite her pride as a queen, she is not above using cunning tactics, such as bluffing, to achieve her goals.

Hiling's primary motivation is the protection and well-being of her family. This drive manifests in different ways throughout the story. At first, her overprotectiveness leads her to severely underestimate Bojji and push Daida to become unnaturally strong to defend his brother. Following King Bosse's death, she conspires with the council to bypass his will and crown Daida as the new king, believing Bojji, due to his perceived weaknesses, would be unable to survive the burdens of the crown and wanting to shield him from that danger. Her single most powerful motivation, however, becomes the rescue of her son Daida when his body is taken over by the soul of the late King Bosse. She disregards her own safety to lead a rescue effort, personally confronting formidable enemies from the Underworld to reclaim her son. She ultimately supports Bojji's journey to grow stronger and become a worthy king, recognizing his inner strength after witnessing his capabilities firsthand.

Within the story, Hiling plays a pivotal role as both an obstacle and, ultimately, a crucial ally for Bojji. Initially an antagonist figure pushing for Daida's ascension, she is instrumental in the kingdom's political direction after the king's death. Her character is central to exploring themes of family, prejudice, and maternal love. After the coup by the Underworld prisoners, she leads the initial defense of the castle, and her healing magic is vital in keeping her soldiers alive during the conflict. She later rallies allies and confronts the reincarnated King Bosse directly, fighting to save Daida and supporting Bojji in the final confrontation. Her character arc forces her to reassess her overprotective nature and recognize her stepson's true potential.

Her key relationships define her evolution. With Bojji, her relationship is the most complex and central to her development. She initially worked hard to gain his trust after marrying his father, learning sign language to communicate with him and playing with him. However, after Daida's birth, her affection morphed into a suffocating overprotectiveness that caused a rift. It is only when she realizes this has alienated Bojji and sees his feats of strength that she loosens her grip and becomes one of his most steadfast supporters, ultimately embracing him emotionally. With Daida, her love is equally strong but expressed through demanding expectations, which fosters resentment in him toward Bojji. Her desperate fight to save him from his father's possession underscores the depth of her devotion. With her personal bodyguard, Dorshe, she shares one of her closest alliances; he is one of the few who understands her true nature beneath her reserve, and she quietly appreciates his steadfast loyalty. Her relationship with Kage begins with scandalized disapproval, but she quickly comes to accept him as Bojji's genuine friend.

Hiling undergoes significant character development. She starts as a seemingly typical "evil stepmother" figure but is revealed to be a nuanced, caring individual. The turning point comes when Bojji, distraught over being passed over for the throne, attempts to flee the kingdom, making her realize the damage her overprotectiveness has caused. From that moment, she begins to relax and allow him more freedom. Witnessing Bojji's prowess in battle against the Underworld prisoners shatters her preconceived notions of his weakness, leading her to fully support his journey. By the end of the major conflicts, she has reconciled with both her sons, shed her overly domineering behavior, and embraces her new role as queen mother, offering Bojji wise counsel in his own rule.

In terms of abilities, Hiling is a master of restorative magic, which she likely learned during her time as a traveling monastic. This potent magic allows her to heal wounds, cure poisons, emit holy light, and with enough power and concentration, even revive the recently deceased. Using her magic takes a significant physical toll on her, rapidly draining her energy and forcing her to drink restorative potions to compensate. Despite its power, her magic cannot regenerate lost limbs. An additional skill she demonstrates is a bluff she calls the Death Promise, a fake curse she uses to intimidate others into good behavior, threatening that any violent action will cause their wounds to reopen and lead to their death. She is also highly intelligent and resourceful, having learned sign language to communicate with Bojji and displaying tactical cunning during battle.