TV-Series
Description
Octavia Tomoe, who also appears under the original name Hotaru Tomoe and transforms into Navegante de Saturno, the counterpart of Sailor Saturn, is one of the central figures of the third season of Sailor Moon, known as Sailor Moon S. She is introduced as a twelve-year-old girl with a frail body, a quiet and gentle manner, and a painful past that largely explains her condition and her place in the story.

Her background is defined by a tragedy that occurred when she was eight years old. A freak storm caused a fire in her father's laboratory, killing her mother Keiko and leaving Octavia herself on the verge of death. Her father, Professor Souichi Tomoe, a scientist, was so desperate to save her that he accepted the offer of a mysterious voice that promised to save them both in exchange for their souls. As a result, a Daimon took possession of the professor, while another entity called Mistress 9 was implanted inside Octavia. In the printed version of the story, her survival also involved her father rebuilding parts of her body with cybernetic technology, making her a cyborg, but in the anime her suffering is presented mainly as the result of the entity living within her.

Because of Mistress 9, Octavia's life was marked by constant health problems, including fainting spells, memory loss, and moments in which she lost control and harmed others without remembering what she had done. One such incident, involving a classmate at the Mugen Academy where she studied, caused her to be feared and ostracized by the other students. She was physically weak and often needed to rest, and she rarely left her father's large and lonely residence. Despite all this, she was not a bitter or hostile child. She was shy, polite, thoughtful, and surprisingly kind, with an intellectual maturity beyond her age. Her creator described her as delicate, quiet, precocious, and somewhat expressionless.

Octavia believed herself to be strange because she possessed supernatural abilities that could both heal and hurt. This uncertainty about her own nature made her isolated and convinced that she was not like other people. Her deepest desire was to have friendship and to be accepted, and she also wished to use her healing gift to help others, dreaming of one day becoming a nurse. She enjoyed quiet activities such as reading and collecting decorative lamps, preferred the color purple, liked Japanese soba noodles, disliked milk, and struggled with physical education and marathons because of her fragile health.

Her role in Sailor Moon S begins when she meets Chibiusa, also called Rini, who becomes her first true friend. Chibiusa is the only person who approaches her without fear and refuses to abandon her, even when the Outer Guardians, especially Haruka Tenoh, warn that Octavia is dangerous. Through this friendship, Octavia experiences the warmth of being cared for, and it is the emotional anchor that eventually allows her to fight against the evil inside her.

In the final events of the season, Mistress 9 finally takes complete control of Octavia's body and uses it to gather pure hearts and summon the entity known as Pharaoh 90 to Earth. When Mistress 9 tears herself away, Octavia's spirit awakens fully and she transforms into Navegante de Saturno, the Guardian of Destruction, Silence, and Rebirth. She is the last of the Sailor Guardians to awaken in this arc and is the most feared because of what she is capable of doing.

As Navegante de Saturno, she carries the Silence Glaive, also known as the Foice or Alabarda do Silêncio, a weapon so powerful that a single swing can destroy a planet or potentially an entire solar system. Her destructive power is said to complement the restorative power of Sailor Moon, and she is also known as the Guardian of Ruin and Rebirth, because her power of annihilation exists to clear the way for new life. In her past life, she was Princess Saturn, the ruler of the planet Saturn, and in ancient times she used her power to destroy the remains of the fallen Moon Kingdom so that the Earth could begin anew. This is why the other Outer Guardians initially considered eliminating her, fearing that her awakening would mean the end of the world.

Despite the danger she represents, Octavia uses her power to save the Earth from Pharaoh 90. In her sacrifice, she unleashes the Silence Glaive's full destructive force to defeat the enemy, even knowing that doing so will consume her own life. Sailor Moon refuses to accept her death and uses her own power to bring her back, causing Octavia to be reborn as an infant. After this rebirth, she is taken in and raised as the adopted daughter of the Outer Guardians Haruka Tenoh, Michiru Kaioh, and Setsuna Meioh, who become her new family. In her new life she is noticeably happier, more open, and more able to smile, though she remains gentle and thoughtful. Her father also survives in the anime and cares for her in later seasons until Setsuna asks for her help in a subsequent arc.

Her key relationships define her entire journey. Chibiusa is the person who first shows her unconditional friendship and love, and their bond is the reason she does not surrender fully to Mistress 9. Sailor Moon is the one who believes in her worth and brings her back from death, embodying the renewal that complements Octavia's destructive power. Her father is a tragic figure, a loving parent who was corrupted by his desperation. Haruka, Michiru, and Setsuna start as warriors wary of her, but eventually become her guardians and adoptive parents, offering her the stable and affectionate home she never had.

In terms of abilities, beyond the planet-destroying power of the Silence Glaive, Octavia can heal minor wounds with her hands, although doing so takes a toll on her own strength. As Navegante de Saturno she also demonstrates defensive techniques such as the Silence Wall, a protective barrier, and offensive techniques such as the Silence Glaive Surprise, which launches a powerful energy blast. In the original manga she also possesses the Death Reborn Revolution, an attack that releases destructive energy that can annihilate everything around her, and she gains additional transformations and powers in later arcs, including a form referred to as Super Sailor Saturn in the anime.

Over the course of her story, Octavia develops from a lonely, frightened, and fragile girl into a determined warrior who accepts her difficult destiny and chooses to protect others at great personal cost. Her journey is one of isolation giving way to love, fear giving way to courage, and destruction giving way to rebirth, which is the very meaning of her role as Navegante de Saturno.