Rudeus Greyrat The protagonist of Mushoku Tensei. Nickname: Rudy. At age 34, he has grown into a man with a sturdy build inherited from his father. Blessed with three wives and six children, he became a subordinate of Orsted to oppose their nemesis Hitogami, eventually establishing himself as the 7th of the Seven Great Powers, the "Magic King."

Sylphiette First Wife: Sylphiette (at age 34). A childhood friend with white hair and immense capacity for kindness. They reunited at the Ranoa University of Magic while she was disguised as a male guardian mage; she healed his trauma and became his first wife. She is the reliable main wife of the Greyrat household, supporting the family from a step behind.

Roxy Migurdia Second Wife: Roxy Migurdia (at age 68). His childhood magic tutor and the reliable mentor he continues to worship as a "Goddess." As a Migurd, she has a long lifespan and a youthful appearance. They were united after a rescue mission in the Teleportation Labyrinth. Despite her small stature due to her demon blood, she is intelligent and thoughtful, supporting the family as a university lecturer.

Eris Third Wife: Eris Boreas Greyrat (at age 36). A swordswoman known as the "Mad Dog King" who grew from a violent young lady into the strongest of warriors. To gain the power to protect Rudeus, she studied under Gal Farion, the 6th of the Seven Great Powers, and trained at the Holy Land of Swords. She rushed to his side during the battle with Orsted and married him. She is the invincible bodyguard who supports her husband in combat.

Lucy Greyrat Eldest Daughter: Lucy Greyrat, approx. 17 years old (Mother: Sylphie). The eldest and most responsible of the children. She feared her father Rudeus as a child but later reconciled. Possessing high magical talent, she eventually enrolls in the Milbotts Academy of Magic in the Asura Kingdom.

Lara Greyrat Second Daughter: Lara Greyrat, approx. 15 years old (Mother: Roxy). A girl with the blue hair characteristic of the Migurd race. While she appears mischievous and taciturn, she is actually the "Savior" foretold to defeat Hitogami. She will eventually set out on a journey to save the world.

Ars Greyrat Eldest Son: Ars Greyrat, approx. 13 years old (Mother: Eris). Born as the eldest son, he inherited his mother's natural talent for swordsmanship. He has had a rambunctious personality since childhood. He falls deeply in love with Rudeus's sister, Aisha Greyrat, which later leads to a major family upheaval.

Sieghart Saladin Greyrat Second Son: Sieghart (Mother: Sylphie). Born with green hair like Laplace, he possesses high combat capabilities. Nicknamed Sieg. Aspiring to be a hero of justice, he eventually earns the title of "Death God" and rises to the 5th of the Seven Great Powers, becoming a hero in his own right.

Christina Greyrat Fourth Daughter: Christina, approx. 6 years old (Mother: Eris). The youngest child, a spoiled girl who grew up doted on by the family. Unlike her mother Eris's fierce personality, she grows into a gentle young lady. She enrolls in the Royal Academy of the Asura Kingdom and eventually marries the kingdom's first prince.