Hotaru's mother, Keiko, died in a fire when Hotaru was only 8 years old. When Hotaru was young, her father, Professor Souichi Tomoe, was performing an experiment in a lab for some others to see. Hotaru noticed something was wrong, but before she could stop him, an explosion happened. Tomoe made it with bruises and cuts, but everyone else was killed. He cried alot, and a strange being appeared and said it could save his daughter in return for their bodies. Tomoe agreed, and he became possessed, along with Hotaru [in the manga, he rebuilt her body into a cyborg]. Hotaru became the vessel for Mistress Nine, a being originating from Tau Ceti, who would summon Master Pharoah 90 to destroy the world. After these events, she started leading a semi-normal life. Hotaru went to Mugen Gakuen, and lived with Kaolinite at her father's side, ordering her around. Sometimes, though, she could be seen sitting on a throne in her Mistress Nine state. Eventually, Mistress Nine took over her body, and almost won, but the Senshi stopped her. Hotaru was killed, and resurrected as a baby, with a chance for a new life. The Outer Senshi took her into their care. She grew at an amazing rate, and soon became a Senshi again.
In the anime and the manga, the original Hotaru is very quiet, shy, and has few friends. People at school are grossed out because of her ability to heal wounds. Physically, she is very weak, and has coughing fits. She doesn't like Kaolinite at all. She is considered a deadly threat by the Outer Senshi since she will become Sailorsaturn, with the ability to destroy the world; the Dark Messiah. When she is a little girl again, she is very sweet, can be very hyper, and is strangely serious as Sailorsaturn. She is best friends with Chibi-Usa, and considers Haruka, Michiru, and Setsuna her family. She has a strange aura about her that heals her and protects her from harm. She grows bigger at an alarming rate and learns very quickly the advanced material Setsuna teaches her. She can also make holographic projections. She is visited by the spirit of Sailorsaturn, who reawakens her abilities. She is the one who gives the Outer Senshi new forms.
In the anime, the Outer Senshi take care of her at the end of SMS because her father is in a wheelchair. Pluto comes to Tomoe when Hotaru is still a baby and takes her from him. Galaxia is responsible for her incredible growth rate, and Haruka and Michiru take her into their care after they are attacked by mirror paredories [parodies? I've seen them referred to as paredories]. Since Chibi-Usa leaves, she doesn't spend time with her anymore.
In the manga, the reborn Hotaru is great friends with Chibi-Usa and spends alot of time with her. She started growing up quickly after the solar eclipse when the Dead Moon Circus appeared.
Hotaru has black, chin-length hair and purple eyes. She has very pale skin. Both of her ears are pierced. In her first state, she usually wore her school uniform, but as a little girl she wears cute dresses alot. She's very short.
As Saturn, she has the powers of creation and destruction, and is powerful enough to destroy the world using her Silence Glaive. Her first fuku is a blue color, in the anime leaning towards purple, with bronze ribbons. Her sleeves are petal shaped, no stripes on her collar, and the top ring on her glove juts out farther than the rest. There is a crystal with many points radiating out of it on her bow and a star on her choker. Her second fuku is purple with black bows and has the typical Super features. She wears knee-length, lace-up boots with high heels, but when she's younger they're normal heels.
Waaaahooo!! Saturn Saturn Saturn!... *ahem* Well, I really like Hotaru! She's just nudged out of being my favorite by Uranus. There's just something about Hotaru, I guess. The idea of this cute, pale, sickly little girl being able to destroy the world... plus the best fuku out of everone... yeah, I really like Hotaru ^-^ I wish she had a henshin and had shown up in the anime more *sigh!*
Senshi Name: Sailorsaturn