Sailor Saturn's age varies. She is four, eight, and possibly ends at the age of twelve. In the manga, she is 12 years old and in the sixth grade. She went to the same school as Michelle and Amara, but now goes to school with Rini.

 

Hotaru Tomoe was once an average, happy girl. She lived in the Tomoe mansion with her father, Prof. Tomoe, her mother having already died. Hotaru's happy life shattered one day when her father was performing some sort of experiment. The young Hotaru was present and very curious. She was leaning over the DNA machine involved in the experiment and was watching when all of the sudden, a large explosion occurred. After the dust cleared, it was learned that Prof. Tomoe had been the only survivor. The professor was grief-stricken with his lifeless daughter in his arms and tears streaming from his eyes. Just then, a glowing black orb appeared. It spoke to Prof. Tomoe, offering to save his daughter. The professor said he didn't care about himself, as long as Hotaru was all right, and so, the orb entered his body and gained control of him. Both father and daughter left the accident without a single scratch. Thus, Prof. Tomoe became part of an evil organization known as the Heart Snatchers. Their ultimate goal was to bring about the end of the world and to cover it with Silence. In order to do so, they must obtain the Purity Chalice, which will form when the three talismans are gathered. The talismans are sealed within the pure hearts of three people. Prof. Tomoe's job was now to create diamond pods that, when bonded with an object, will become a monster called a Diamond Heart Snatcher. These Diamonds were to assist in the collection of pure hearts

            

             Hotaru continued life, miserably. She would often have seizures in which she would hurt her classmates. When these seizures ended, she would have no memory of the events that took place during them. This led everyone to fear Hotaru so much that they won't even speak to her and left her without any friends except for Rini. As time went on, the Sovereign Of Silence would take over every time she would have a seizure. All the kids at school make fun of her because she has strange powers. She has healing powers that allow her to heal other peoples injuries.

 

             Mistress 9 was the evil that corrupted Sailor Saturn's soul and turned her against the other Sailor Scouts. Mistress 9 had Professor Tomoe lead the Heart Snatchers in hopes of releasing the entity known as Pharaoh 90, who had dreams of conquering Earth.

 

             She is tied in the running for the most powerful Sailor Scout with Sailor Pluto. Sailor Saturn can destroy the world with her Silent Side, but Sailor Pluto can use her forbidden attack to stop time and stop her.

 

             She is a really sweet girl as Hotaru, but as Sailor Saturn, she is dangerously scary