Celia Vulgast Llinger is the princess of the Llinger Kingdom in the anime The Wrong Way to Use Healing Magic. She is the daughter of King Lloyd Vulgast Llinger, the ruler of the kingdom, which places her within the royal household at the center of the story's setting. She is a young woman with blonde hair and blue eyes who carries herself with an elegant and refined manner. Her behavior is polite and ladylike, and she is known for being attentive and considerate toward the people around her, showing care in her interactions with others.

Within the story, Celia serves as a supporting figure of the royal court rather than a combatant or adventurer. Her most prominent personal storyline is her quiet interest in Kazuki Ryuusen, one of the young men summoned to the kingdom as a hero; she is drawn to him and takes notice of him during his time at the castle. Her relationship with her father connects her to the kingdom's authority, and her composed, gracious personality reflects the dignity expected of her position as a princess.

Celia does not have a major character arc of her own, and her development in the anime is subtle, centered mainly on her growing attention toward Kazuki and her steady, supportive presence within the royal setting. Her defining qualities are social rather than combat-oriented, with courtesy, composure, and consideration for others shaping her role. No magical abilities or fighting skills are emphasized in connection with her character; she is presented primarily as a princess whose significance comes from her place in the royal family and her gentle, watchful nature.