Merlin is an S-rank wizard and the mentor and foster mother of Lloyd, who adopts him after his hometown is destroyed by the demon king. Driven by grief from losses she suffered in her own past, particularly the sacrifice of a hero named Cibil, Merlin trains Lloyd with relentless toughness. Her teaching style blends sarcasm, harsh lessons, and a stern, no‑nonsense attitude, yet she holds a deep, caring concern for his well‑being. She has a fondness for alcohol and is known to be somewhat eccentric. Merlin’s primary motivation is to nurture Lloyd’s hidden potential while preventing him from becoming overconfident or repeating the mistakes she witnessed in her youth. To that end, she secretly casts a spell on Lloyd that guards against arrogance and steers him toward a path as a white mage, emphasizing support and recovery magic. She also dissuades him from learning ancient magic, fearing its dangers. After Lloyd leaves her home to become an adventurer, Merlin continues to watch over him through an informant, worried that he might be exploited or misled. In the course of the story, she appears at critical moments to offer guidance, magical expertise, and direct assistance, such as during the climactic battle against a demon‑possessed chimera. Her extensive knowledge of holy swords, ancient magic, and the workings of the world makes her a crucial figure behind the scenes. Despite not being related by blood, she treats Lloyd as a son and expresses genuine pride in his growth. Merlin’s own haunted past, shaped by her battles alongside Cibil, adds emotional depth to her character and underscores her determination to see Lloyd succeed where others have fallen.