Civilian
Hotaru is often seen with shoulder-length black hair featuring a subtle purple sheen at the front and purple eyes. In her initial appearances, she frequently wears casual clothing or a winter jacket while under the influence of Mistress 9.

Like Haruka and Michiru, who also posed as Mugen Academy students, Hotaru wears the academy’s standard winter uniform, pairing it with blue pantyhose and black flats.

Sailor Saturn
As Sailor Saturn, Hotaru keeps her civilian appearance but gains a gold tiara with a white gem on her forehead. Her uniform’s main color is purple, seen in her sailor uniform, choker, gloves, and skirt. Her leotard sleeves resemble flower petals, and she wears purple knee-high heeled boots with white laces. Her front and back bow is dark brown in the anime’s official art but appears black in the third season. Both her silver star brooch and the star gem on her choker resemble the Pure Heart Crystals targeted by the Death Busters. She also wears silver, planetary earrings resembling Saturn and wields the Silence Glaive.

Super Sailor Saturn
In her Super Sailor form, Hotaru’s uniform adopts indigo as the dominant color. Her collar has a single white stripe on each side, and her back bow is lengthened. The gem at the center of her bow changes to a purple heart-shaped brooch, and her choker features a gold star at the center.

Hotaru Tomoe is a reserved and introspective individual, often portrayed as shy and solitary due to her frail health and mysterious powers. Her quiet demeanor and frequent isolation make her seem withdrawn, yet she possesses a deep kindness and loyalty, especially shown through her close friendship with Chibiusa, whom she cherishes deeply.

As Sailor Saturn, Hotaru’s personality shifts to embody a serious, determined nature. In this role, she is unwavering in her duty as the Guardian of Silence, Death, and Rebirth, contrasting with her gentle civilian persona. Through her journey, Hotaru grows from a timid, sickly girl into a resolute and confident individual, embracing her identity and responsibilities with strength and resilience.

Background
Hotaru is the only child of Professor Souichi Tomoe. As a child, she was involved in a catastrophic accident at her father’s genetic engineering lab when Germatoid, a Daimon from the Tau Star System, used the professor’s experimental setup to cross over to Earth, resulting in a massive explosion. Although the incident left Hotaru dead and her father injured, Germatoid offered to revive her if Souichi agreed to his terms. In desperation, the professor accepted, leading to Germatoid possessing his body and Mistress 9 inhabiting Hotaru’s resurrected form. While Germatoid fully overtook Souichi’s personality, Mistress 9 remained dormant within Hotaru, surfacing only on rare occasions. Left frail and prone to mysterious seizures, Hotaru attempted to live a normal life, but her unusual healing abilities and mood swings led to her isolation. Meanwhile, her possessed father secretly prepared Earth for Pharaoh 90’s arrival, unbeknownst to Hotaru.

Hotaru’s classmates distanced themselves due to her strange abilities and frequent mood changes, leaving her to live a solitary life.

Sailor Moon S
When Sailor Moon first uses the Holy Grail to transform into Super Sailor Moon, a brilliant light triggers dark energy within Hotaru. A few days later, she meets Chibiusa in the park, and they quickly become best friends. Hotaru’s mysterious seizures, stemming from the lab accident, sometimes cause her to collapse unexpectedly.

During Daimon attacks, Hotaru unconsciously reveals her latent powers, damaging a few Daimons that cross her path during these episodes. Her displays of power draw the attention of the Outer Sailor Senshi—Uranus, Neptune, and Pluto—who begin to suspect she could be the prophesied “Messiah of Silence.” Sailor Pluto reveals that Hotaru is the reincarnated Sailor Saturn and fears that Saturn’s awakening could lead to the destruction of the world.

When Hotaru’s identity as Sailor Saturn is confirmed during a Daimon attack, the Death Busters hide her within Mugen Academy to prevent the Outer Senshi from reaching her. However, the Outer Senshi remain convinced that she must be eliminated before the next eclipse to prevent her from ending the world. Under the control of the Messiah of Silence, Hotaru continues following Professor Tomoe’s orders.

Eventually, Chibiusa is captured by the Death Busters, and the Messiah of Silence takes Chibiusa’s Pure Heart Crystal, transforming Hotaru into Mistress 9. While possessing Hotaru’s body, Mistress 9 struggles to maintain control as Hotaru’s spirit resists. After Mistress 9 opens a path for Pharaoh 90, Hotaru ultimately reclaims control, destroying Mistress 9 and reawakening as Sailor Saturn.

Willing to sacrifice herself to save the world, Sailor Saturn uses her powers to destroy Pharaoh 90. However, Sailor Moon, using her Pure Heart, enters Pharaoh 90’s core to save Hotaru, emerging with an infant Hotaru in her arms. With Germatoid no longer possessing him, Professor Tomoe gratefully takes his daughter back under his care, planning to raise her again.

Sailor Moon Sailor Stars
In the fifth season, infant Hotaru lives peacefully with her father. However, she has a vision of Neo-Queen Serenity and Eternal Sailor Moon under a vast full moon. Soon, Setsuna arrives to take Hotaru with her, as her powers will be needed in the coming battles. Understanding her destiny as a Sailor Guardian, Professor Tomoe entrusts Hotaru to Setsuna’s care.

Hotaru’s rapid growth accelerates over the following days, eventually bringing her to an age just slightly younger than Chibiusa. Initially, she has no memory of her previous life, until the spirit of Sailor Saturn appears and restores her memories. She is then fully reawakened as Super Sailor Saturn, the Sailor Guardian of Death and Rebirth, now focused on her mission with a renewed sense of duty. Her personality as Sailor Saturn differs from her human identity, reflecting the influence of her guardian spirit.

Although absent for most of theSailor Starsepisodes, Hotaru is present throughout the Nehellenia arc and reappears briefly at the series’ end. She does not transform into Super Sailor Saturn on-screen via Crystal Power, though Sailor Pluto later returns with her in this form, granting her the same Crystal Power upgrade alongside Sailor Uranus and Sailor Neptune.

Later in the season, Sailor Pluto is defeated by Sailor Galaxia, who takes her Star Seed alongside Sailor Saturn’s. However, Hotaru and the other Super Sailor Senshi are ultimately revived by Princess Serenity, who restores Galaxia’s original self by expelling Chaos from her body. Grateful, Sailor Saturn watches as Serenity is joyfully reunited with Mamoru (now in the attire of Prince Endymion) and bids farewell to Chibi Chibi.

Sailor Saturn wields powers tied to death, destruction, silence, and ruin. With her immense abilities, she can obliterate entire planets, reducing them and their inhabitants to complete oblivion. At her full potential, she holds the power to bring devastation to entire worlds.

In addition to her offensive capabilities, Sailor Saturn can create powerful force fields around herself and others, capable of withstanding even the strongest attacks from enemies like Galaxia.

Attacks

• Silence Wall: A defensive barrier that shields her and her allies from attacks.
• Silence Glaive Surprise: A devastating offensive attack channeled through her glaive.

Items

• Silence Glaive: Her iconic weapon, essential for channeling her powers of destruction and silence.

Hotaru: The kanji for “Hotaru” (蛍) translates to “firefly.” In Japanese mythology, fireflies are often linked to the spirits of the deceased, adding a layer of symbolism to her character.

Tomoe: The kanji in “Tomoe” (土萠) translates to “earth” (to, 土) and “sprouting” (moe, 萠). Interestingly, the kanji 土 is also the first character in the Japanese name for Saturn, “Dosei” (土星).

Combined, her name can be interpreted as “firefly sprouting from Earth,” symbolizing both her connection to life and death and her role as Sailor Saturn.