Rudeus Greyrat, formerly a shut-in NEET in his past life, has been reborn as a handsome young man with flaxen brown hair and aqua-blue eyes. Wearing his trademark grey magic robe, he possesses the "Eye of Foresight" in his right eye, allowing him to see a few seconds into the future. Driven by his vow to never waste his life again, he is a hardworking and gentle person. However, his self-esteem is abnormally low, and his past life's sleaziness and vulgar inner thoughts occasionally manifest as a disgusting smirk. While he is a heavy lecher, he treats women like a gentleman. Yet, toward enemies who threaten the safety of his family or friends, his usual gentleness vanishes, revealing a cold, ruthless, and fierce nature.

Sylphie is a quarter-elf with human and demon blood, a beautiful girl with pointed ears and a dreamlike, adorable appearance. In her childhood, she was bullied because of her green hair, which was associated with the Superd race. However, due to the trauma of the Teleportation Incident and an excess consumption of mana, her hair has since turned a mystical white. She speaks in a gentle and honest manner, but at her core lies an absolute love for and dependence on Rudeus. While she is a devoted pacifist who prioritizes the happiness of others, she harbors a strong obsession and drive to be useful to him and stand by his side as an equal. She usually maintains a mild temperament without showing jealousy or dissatisfaction, but when Rudeus's health is threatened or when he doesn't lean on her, she displays a stubbornness and inner strength that one wouldn't expect from her usual self.

Roxy Migurdia is a mage of the long-lived Migurd race. She is characterized by her translucent blue twin-tails, deep blue eyes, and a doll-like appearance that remains unchanged from that of a girl in her early teens. She harbors a complex about being treated like a child despite her actual age. Wearing a large witch's hat and a chic magic robe, she speaks calmly and intellectually in polite language. While she is very serious and takes great pride in her magic, she also has a clumsy side, making fatal blunders at critical moments, and a worrying, awkward personality. She is usually cool-headed, but when flustered by unexpected events or when in front of Rudeus, her girlish emotions leak out, hiding a strong maidenly desire to be seen as a mature woman.

Zanoba Shirone is the third prince of the Kingdom of Shirone and a figure enthusiast who looks up to Rudeus as his master. He is a "Blessed Child" born with superhuman strength. In the past, he was feared as the "Decapitating Prince," but after being shocked by the artistic beauty of a figure made by Rudeus, he became his apprentice and now pours all his passion into doll-making. He usually speaks with a haughty, princely tone, but he swears absolute loyalty to Rudeus. Despite his delicate nature and his struggle with being unable to craft fine dolls himself due to his monstrous strength, he is incredibly loyal to his comrades and possesses a fiery devotion that will follow his master anywhere.

Ariel Anemoi Asura is the second princess of the Asura Kingdom, a charismatic beauty who eventually competes for the throne. With shining blonde hair and overwhelming beauty, she is a natural leader who fascinates many with her elegant demeanor and excellent oratory skills. She usually wears the mask of a generous and perfect royal, but internally she is cold and calculating—a shrewd opportunist who will choose any means to achieve her goals. At the same time, she holds deep affection and absolute trust for her inner circle, such as her guardian mages Sylphie and Luke, who have supported her. Having survived numerous life-threatening crises and political struggles, she has honed a fierce obsession with taking the throne and a resilient spirit that refuses to yield to adversity.

Nanahoshi Shizuka is a girl who, like Rudeus, was transported from modern Japan to this different world. She has the appearance of a pure Japanese girl with black hair and black eyes, always wearing a white mask and school-uniform-like clothing. Because she possesses no mana, she cannot use magic, but she uses her knowledge of modern Japan and her natural intelligence to dedicate her life to researching "Summoning Magic" to return to her original world. Her personality is strong-willed, rational, and realistic, but she is constantly plagued by intense loneliness and homesickness from being left behind in an unknown world. She and Rudeus are unique allies who both know modern Japan, and while they occasionally clash, they have built a relationship of deep trust.

Cliff Grimoire is a talented genius mage whose grandfather is the High Priest of the Holy Kingdom of Millis. Characterized by slightly wavy brown hair and a cheeky face, he was raised as a genius since childhood. Consequently, he was proud and self-confident, and his arrogant behavior was prominent at first. However, after witnessing Rudeus's overwhelming power and realizing his own immaturity, he underwent significant personal growth by working hard through his setbacks. Internally, he is very pure with a strong sense of justice and a kind heart that cannot ignore people in trouble. He fell in love with Elinalise, a cursed long-eared woman, and he is a man of great integrity who pours his passion into magic tool research to break her curse, showing sincere and fiery devotion to those he loves and his comrades.

Aisha Greyrat is Rudeus's half-sister. A genius girl with a brilliant mind and great resourcefulness, she adores her brother fanatically. She handles everything around him perfectly as a maid, but because of her brilliance, she harbors loneliness and distortions, leading her to make turbulent choices.