Kalego hails from the prestigious Naberius family, a renowned noble demon lineage known for its discipline, power, and strict adherence to hierarchy. From a young age, Kalego was trained to excel in magic and combat, eventually becoming a highly respected professor at Babyls, where he is feared and respected by students and faculty alike. His unwavering dedication to discipline and excellence makes him a formidable figure, shaping students into capable demons under his rigorous instruction.

During his years as a student at Babyls, Kalego was classmates with Balam Shichiro and Opera, forming a notable trio of future elite demons. While he maintains professionalism in his role, his history with Opera often leads to humorous moments, as he finds himself outmatched in their personal interactions.

His biggest personal frustration stems from his accidental contract with Iruma, which forces him to serve as Iruma’s familiar whenever summoned. Though he despises the situation, he reluctantly plays along, unaware of the deeper implications of Iruma’s existence.

Kalego is tall, lean, and sharp-featured, exuding an aura of strict authority and discipline. He has pale skin, dark purple eyes, and jet-black hair slicked back neatly, reinforcing his intimidating and composed demeanor. His usual attire consists of the Babyls faculty uniform, which includes a dark purple high-collared coat with gold trim, signifying his elite status as a professor.

When summoned as Iruma’s familiar, Kalego undergoes a drastic and comedic transformation, appearing as a small, chibi-like Cerberus with fluffy fur, round eyes, and tiny horns. Despite his adorable appearance, he maintains his grumpy and annoyed personality, frequently growling and protesting against Iruma’s casual treatment of him.

Kalego is strict, disciplined, and highly professional, taking his role as a teacher very seriously. He demands excellence from his students, showing little tolerance for laziness or incompetence. Due to his rigid mindset, he is often perceived as cold and unapproachable, earning a reputation as one of the toughest instructors at Babyls. However, his harsh teaching methods stem from a genuine belief in discipline, as he aims to push his students to reach their full potential.

Despite his serious demeanor, Kalego has a deeply sarcastic and dry sense of humor, often delivering biting remarks with a deadpan expression. His interactions with Iruma are especially comedic, as he finds himself constantly frustrated by Iruma’s antics, yet is unable to outright punish him due to their contract. Though he resents being Iruma’s familiar, he begrudgingly fulfills his duties, showing a reluctant sense of responsibility toward his students, even if he refuses to admit it.

While he seems detached and ruthless, Kalego does care for his students in his own strict way, offering guidance and discipline when necessary. He is a firm believer in personal strength and merit, respecting those who prove their abilities, even if he rarely openly acknowledges their growth.

• Homeroom Teacher of the Abnormal Class
  Kalego is responsible for overseeing the Abnormal Class, a group of unique and unpredictable students, including Iruma, Alice, and Clara. Though he is initially frustrated by their antics, he gradually recognizes their potential, guiding them through rigorous training and combat lessons. His strict but effective teaching methods ensure that the Abnormal Class grows into formidable demons.

• Iruma’s Unfortunate Familiar
  Due to an accidental contract mishap, Kalego becomes Iruma’s summoned familiar, transforming into a tiny Cerberus against his will. This leads to constant comedic interactions, as Kalego despises the situation but is powerless to change it. Despite his reluctance, he continues to fulfill his role, offering unintentional support and protection to Iruma.

• Rivalry & Friendship with Opera
  Kalego shares a complicated history with Opera, as the two were former classmates. While Kalego tries to maintain his usual authority, Opera often outmaneuvers and outsmarts him, leading to frequent comedic moments where Kalego is forced into an inferior position. Their longstanding rivalry and professional relationship add depth to his character dynamics.