Guest is his twin brother! Sylphie's husband! Ultra-cautious and humble: Due to the trauma of failing his previous life, no matter how much those around him worship him as a genius, he never lets it go to his head and always acts assuming the worst-case scenario. A gritty hard worker: Having sworn to "live life for real this time," he possesses the tenacity to fight through anything, even discarding his pride and crawling through the mud, to protect his family and friends. An open pervert: He has an extremely strong interest in women and his mind is always in the gutter, but at the same time, he constantly struggles with the rational brake of wanting to "live sincerely."

Rudy's first wife! Overwhelming tolerance: An absolute ally who supports Rudeus with total affirmation. She is the reliable legal wife of the Greyrat family who accepted Rudeus taking Roxy as a second wife with a broad heart. Serious and hardworking: In her childhood, she was timid and dependent on Rudeus, but out of a single-minded desire to catch up to him and stand by his side, she worked desperately on her magic and became independent. Inherent ferocity: Usually gentle and calm, but toward enemies who threaten her "precious ones" like her family or her lord (Ariel), she possesses the coldness and strength of a warrior who swings her staff without mercy.

Rudy's second wife! Serious and intellectual: Possesses high professionalism and a sense of responsibility. With her wealth of experience, she can always make realistic and rational judgments, acting as the brake (the adult voice of reason) for the often-reckless Greyrat family. Humble with low self-esteem: Due to the trauma of being born unable to use her village's telepathy, she carries deep-seated loneliness. Even after becoming a top-tier mage at a young age, she remains humble, believing she is "not a genius." Gap between cool exterior and girlish innocence: She looks cool with a poker face, but she's simply bad at expressing emotions. She has a maiden-like side that secretly longs for a "fated love" like in stories, and occasionally blushes after making a clumsy mistake.

Guest's wife! Overwhelming wildness and ferocity: In her childhood, she was the type to throw a punch before speaking—a "mad dog" personality that was prideful and difficult to handle. Madly single-minded: She loves Guest from the bottom of her heart and possesses overwhelming tenacity, having put in life-or-death effort at the Holy Land of Swords solely to gain the strength "worthy of standing beside him." Honest and clumsy: She hates lies and secrets, and her emotions are always 100% straight. Her clumsiness sometimes causes misunderstandings, but the innocent maiden face she shows only in front of Guest is her greatest charm.

The first child of Sylphie and Rudy! Serious and responsible: Raised as the eldest child of the Greyrat family, she is very reliable and a kind older sister who takes good care of her younger half-siblings. Clumsy father-complex: She deeply respects her father, Rudeus, but harbored complex feelings, misunderstanding that "perhaps my excellent father doesn't have expectations for me," leading to a cold attitude during her rebellious phase. A proud hard worker: To further polish the talent for voiceless incantation inherited from her parents, she is the studious type who maintains perfect conduct and top grades at school.

The first child of Roxy and Rudy! An ultra-laid-back brat: Usually loves to lounge around, being quiet and poker-faced. However, she is very sharp-witted and is a problem child who spends all that high intelligence on elaborate pranks on her family. Thick-skinned and gutsy: Even in front of Orsted, the world's strongest Dragon God, she isn't intimidated at all; rather, she maintains a fearless and insolent attitude, even going as far as to play pranks on him. A savior's bird's-eye view: Born with high-precision telepathy, she senses the future trends of the world alongside her partner, the Sacred Beast Leo. She possesses a unique sensibility, looking at the world from a distance as if it were someone else's business.

The first child of Eris and Guest! A mischievous and straightforward wild child: Inheriting the same burning red hair as Eris, he is a rowdy boy who loves swordsmanship and playing outside more than studying. He hates lies and deception and has a pure side that often gets tricked by his older sister, Lara. Inherited "closet pervert" traits and tolerance: He has clearly inherited Guest's lecherous side, but at the same time, he possesses a gritty kindness that "accepts a woman's weaknesses entirely and wraps them in gentleness." Breakthrough power for the sake of love: When he fell into a forbidden love with his aunt Aisha, he showed the terrifying tenacity and manly resolve typical of the Boreas bloodline, refusing to let go of her hand even when the whole family was furious and opposed, eventually running away from home.

An all-purpose super genius: Since childhood, she has been the sharpest mind in the Greyrat family, producing results that put adult professionals to shame in every field, including housework, studies, tactics, and magic. A calculatedly cute brother-complex: She is skilled at acting in a way that utilizes her own cuteness and is fanatically attached to Rudeus and Guest, calling them "Big Brother." She has a devilish side, sometimes wrapping them around her finger. Tenacity bordering on distortion: Due to her background as the "daughter of a maid," she has a habit of coldly observing those around her. This warped perfectionism hides a ferocity that later leads to the "house-shaking forbidden pure love incident" with her nephew Ars.