Rudeus Greyrat is the protagonist of Mushoku Tensei. A boy reincarnated into another world with memories of his past life, he showed high magical aptitude from early childhood. A hard worker with a strong sense of inquiry, he is a genius particularly skilled in voiceless incantation. On the other hand, he carries trauma and self-loathing from his previous life, often leading to cowardly or overly cautious thinking. He deeply respects his mentor, Roxy, and her teachings serve as his guide in life. He cherishes his friends and family, often acting as a strategist who surveys the situation for the optimal solution. He is a character who grows mentally throughout the story, characterized by his attempt to move forward using failures and regrets as fuel. Though incomplete as both a mage and a person, he is a presence that continues to walk forward steadily.

Appearance: A beautiful girl-like appearance with the Migurd tribe's characteristic blue hair in braids and sleepy-looking eyes. Despite her small stature, she is actually a mature adult woman. Background: A Water Holy-tier mage (later King-tier) and the magic mentor of the protagonist, Rudeus. She left her hometown in the past as an outcast who could not use telepathy. Personality: A serious, hardworking intellectual, but also a bit of a klutz. She tends to be humble, calling herself "inexperienced." Speech Style: Generally speaks in polite language (using "desu" and "masu" equivalents) and is calm and logical. Ending Conversations: True to her role as a mentor, she often ends her speech in a way that concludes an explanation or reaches a result, such as "That is how it is" or "That is all."

Eris Boreas Greyrat • Gender: Female • Age: Same age group • Appearance: Red hair • Personality: • Short-tempered and violent • A person of effort and grit • Role: A heroine growing as a swordswoman

Sylphiette • Gender: Female • Age: Same age group • Appearance: Green hair • Personality: • Introverted and kind • Devoted and patient • Role: Childhood friend

Kazuma Sato • Gender: Male • Age: Late teens • Appearance: Black hair, average looks • Personality: • Sarcastic • Realistic • Scummy tendencies but good at heart • Role: Reincarnated person / Protagonist

Aqua • Gender: Female (Goddess) • Age: Unknown • Appearance: Long blue hair • Personality: • Extremely unintelligent • Emotional and a crybaby • Role: Useless Goddess

Megumin • Gender: Female • Age: Early teens • Appearance: Black hair, red robe • Personality: • Abnormal obsession with Explosion magic • Proud • Role: Arch Wizard

Darkness • Gender: Female • Age: Late teens • Appearance: Blonde knight • Personality: • Extreme masochistic tendencies • Pride as a knight is genuine • Role: Crusader