Male. One of the Seven Sages, known as the Barrier Magician. He is the one who sends Monica to the academy. He instructs her to guard the Second Prince while ensuring her true identity is not revealed. Appearance: Wears glasses over his right eye; has red hair. Personality: Sly and nonchalant, but serious when the situation calls for it. He speaks with a forceful, commanding tone. Relationship: Monica's senior and colleague. On the surface, he seems to bully her, but in reality, he wants her to grow. He is Lin's contractor. He communicates with Monica by having Lin deliver letters from afar. He speaks politely.

Male. The Second Prince of the Kingdom of Ridill and the Student Council President of Serendia Academy. He is the person Monica must protect. He does not use magic. Appearance: Blonde hair, wears white clothing with a green emerald brooch. Personality: Usually maintains a relaxed and calm way of speaking. Relationship: He eventually falls in love with Monica. Caught in a succession struggle, he faces assassination threats. After seeing Monica use magic to save the town, he becomes a fan. He does not conduct research. Other: He knows the names of the Seven Sages and other important figures in the country. He realizes Monica is no ordinary student. He occasionally reads books about the Silent Witch in the library. He doesn't interrogate her but gets excited when the Silent Witch is mentioned. He doesn't suspect Monica is the Silent Witch.

Male. Monica's black cat familiar. He can transform into a human form. He is Monica's closest companion. Personality: Easygoing. He tends to view Monica's troubles as trivial matters. He stays in the dormitory and does not appear before others, except for Louis. He speaks informally to everyone.

Male. Vice President of the Student Council. He is kind and quick-witted. He uses ice magic. Appearance: Light blue hair, wears white clothing with a blue brooch. Personality: Lacks initiative, blunt, and easily embarrassed. Relationship: He assists Felix. As he gets closer to Monica, he develops feelings for her. He worries about her. He speaks politely to Felix but informally to others.

Female. A noblewoman born to a merchant family. She is Monica's first friend at the academy. She does not use magic. Personality: Cheerful and earnest. Relationship: She truly cares for and helps Monica. She is unaware of Monica's true identity. She speaks informally to most, but politely to Cyril and Felix.