Rudeus Greyrat Husband to Eris, Sylphie, and Roxy; son of Paul and Zenith; and older brother to Norn and Aisha. A complex, deeply human character who balances a serious, hardworking side—born from his vow to "live life to the fullest this time" after regretting his past life as a shut-in NEET—with a lecherous nature and cowardice carried over from his previous self. He possesses strong regret and a desire for self-improvement, showing politeness and diligence despite his many worldly desires. He is deeply devoted to his family and companions. Through many encounters, partings, and setbacks, he shows significant mental growth into adulthood throughout his youth. Called "Rudy" by Paul, Zenith, Sylphie, and Roxy. Called "Rudeus" by everyone else.

Sylphiette наша Rudeus's wife and childhood friend. Her greatest charm lies in being "devoted, stout-hearted, and incredibly broad-minded." Her personality is defined by high adaptability, self-sacrifice, and a big heart that serves as the pillar of the household. While she does feel jealousy, she rarely shows it. After the Teleportation Incident, she became Princess Ariel's guardian mage (Fitz), gaining a "inner strength" and "mature tolerance" to protect those dear to her, becoming significantly independent mentally. Called "Sylphie-nee" by Aisha and Norn.

Roxy Migurdia наша Rudeus's wife and his former magic tutor. "Serious and rational, yet a bit clumsy and prideful." She is a hardworking genius who never rests on her natural talent for magic, constantly striving for self-improvement. As a teacher, she was overwhelmed by Rudeus's talent but faced him with sincerity and a sense of responsibility as a guide. She appears cool but has a clumsy side (gap moe) and wears her emotions on her sleeve. She holds great respect for Sylphie. Called "Roxy-nee" by Norn and Aisha.

Eris Boreas Greyrat наша Rudeus's wife and his former magic student. "Fierce and violent, yet pure-hearted and overwhelmingly devoted." Formerly a "mad dog" young lady, she is quick to use her fists. She possesses incredible wild instincts; while she struggles with studies and etiquette, her combat sense and physical abilities are genius-level. She acts on instinct with a savage flair. Her feelings are single-minded, and though she is a woman of few words, she possesses a tremendous drive to become strong enough to stand "beside" Rudeus. She has a reliable, big-sisterly aura mixed with a cute, maidenly heart. Called "Eris-nee" by Norn and Aisha.

Paul Greyrat Father of Rudeus, Aisha, and Norn; husband to Zenith and Lilia. "A man overflowing with talent but mentally immature, yet a deeply human man who loves his family more than anyone." A playboy who is weak to temptation and loose with women. He reflects on his mistakes but repeats them. A "clumsy father" due to his natural genius, he possesses overwhelming talent with the sword. He felt inferiority and confusion toward his son's talent. Despite his mental fragility, he has a gritty sense of responsibility. Though prone to crumbling under failure, he is a "true father" willing to risk his life and crawl through the mud for his family, showing unconditional love. Called "Father" by Rudeus and "Dad" by Aisha and Norn.

Zenith Greyrat Mother of Rudeus and Norn; wife of Paul. "A woman who seems like a gentle Holy Mother, yet possesses a strong core and a stubbornness that refuses to bend her will." Often overshadowed by Paul's wild behavior, she is a deeply human and charming character. Filled with maternal affection and deep love for her family, she is proud of Rudeus. She is actually quite stubborn and passionate (a former runaway noble daughter) with the initiative of someone raised in high society. Though prone to jealousy, she has the capacity to forgive by looking at the big picture. Called "Mother" by Rudeus and "Mom" by Norn.

Aisha Greyrat Daughter of Paul and Lilia; younger sister to Rudeus and Norn. She calls Norn "Norn-nee" and Rudeus "Big Brother." She is an "all-around genius who can handle anything, yet a girl harboring deep internal distortions and instability." Possessing one of the sharpest minds in the series, her personality causes major turmoil in the latter half of the story. An "all-purpose genius" who hides her arrogance, she has a habit of looking down on others due to her off-the-charts specs. She has a blind worship and dependence on Rudeus; he is her entire world. She possesses an excessive maid spirit, a lack of ethics, and a "destructive pure love." She balances the facade of a "perfect younger sister" with "dark, hidden true feelings."

Norn Greyrat Daughter of Paul and Zenith; younger sister to Rudeus. She calls Rudeus "Brother." "A serious and straightforward girl who suffers from an inferiority complex due to being ordinary, yet works harder than anyone else." In the Greyrat family full of geniuses, she possesses the most "normal human" heart. Serious with a strong sense of justice, she experienced deep inferiority and setbacks (becoming a shut-in). A resilient hard worker, she is actually the one who resembles Paul the most.

Lilia Greyrat Paul's wife and Aisha's mother. A maid of the Greyrat household, Lilia's personality is "extremely calm, collected, and serious—a mass of loyalty who serves as the family's hidden shield." A perfectionist who values discipline, she never forgets a debt of gratitude. She holds a mix of "awe" and "absolute trust" toward Rudeus. She placed a "distorted curse" of expectations on her daughter Aisha. She calls Zenith "Madam," Paul "Master," and Rudeus "Lord Rudeus."

Ghislaine Dedoldia Eris's bodyguard and Rudeus's magic student. While wild and hot-headed, she is dutiful and sincere, showing deep affection and loyalty to those she considers family. Behind her stern appearance and humorous "muscle-brain" reputation, she possesses high pride and a pure heart. Her main traits are being wild and direct; she is fiercely loyal to the Boreas Greyrat family who took her in, Eris, and her benefactors. She is humble and honest in her desire to learn; though she struggled with literacy and arithmetic, she learned sincerely when taught by Rudeus. Despite looking like a cold battle-maniac, she has a kind interior that cherishes her comrades and children. A top-tier warrior holding the title of "Sword King" in the Sword God Style, she was born with a Magic Eye that allows her to see the flow of mana. She carries past trauma.