Otonashi

Saya Otonashi (音無 小夜 Otonashi Saya) is the main protagonist of the series. Saya is the daughter of a chiropteran mummy named Saya which was brought from Iceland by Joel the first.

Appearance
Saya has the appearance of an average rosy-cheeked, teenage, high school girl with a height of 5'2" and weighing 89lbs. She is black-haired with different hairstyles throughout time. In Okinawa, she likes to keep her bangs and hair short. After Riku's death, her bangs are shown to have grown, giving her a much matured look. Back in the zoo, she used to have long hair with bangs tied behind. Her dark red eyes change to glowing crimson whenever she feeds on blood, change to chiropteran mode or sense the presence of Diva.

Life in the Zoo
Saya was "born" in 1833 from one of two cocoon-like objects taken from the belly of a chiropteran mummy, the other cocoon containing her sister Diva. Both are kept at the "Zoo" by Joel Goldschmidt, where Saya is treated as his daughter and Diva, who is left nameless, is confined to a tower. Saya does not learn about Diva's existence until 1863, when she hears Diva singing and finds her locked in a room at the top of the tower. Saya then names her Diva. In 1870, Amshel purchases a twelve-year-old boy named Hagi from his parents to become Saya's companion and friend. During a birthday party for Joel in 1883, Saya releases Diva so that she can sing for Joel. Diva, however, slaughters everyone in the Goldschmidt house while Saya and Hagi are out looking for Joel's favorite flower. Recognizing that Diva is a monster, Saya spends her periods of activity hunting Diva to try to kill her, her chevaliers, and any chiropterans they have created.

During the Russian Revolution
During a flashback dream she is hunting Diva after the presumed death of Grigori. This takes place after the Russian Revolution. It turns out the girl Sonia is Grigori. Grigori is crystalized after Diva escaping with Amshel. After that Saya goes into her deep sleep(30 years hibernation).

Sudden Awakening during the Vietnam War
During the Vietnam War, a mass bombing occurs on December 25, 1972. The Red Shield agents attempt to prematurely awaken Saya when chiropterans are set loose in Vietnam, hoping that she will be able to fend them off. Their efforts go wrong when she awakes in a frenzy and kills friends and foes alike. Saya hears Diva singing and follows the sound to an empty container. Joined by Hagi, she fights Karl and almost kills him, but he cuts off his crystallizing arm to save himself. Karl flees to a small village and Saya follows. Hagi tries to stop her but Saya cuts off his arm and slaughters humans and chiropterans alike, in the process fatally injuring David's father. This rampage is witnessed by both an US military soldier George Miyagusuku and a reporter, Akihiro Okamura's father (who takes pictures of Saya attacking). After exhausting herself, Saya falls asleep, returning to her hibernation. David's dying father entrusts her safety to George, who stores her in the Miyagusuku crypt when he later moves to Okinawa, Japan.

A New Beginning
Saya's cocoon lies inside the Miyagusuku crypt in Okinawa for years where George has moved with his family after leaving the military. But a sudden accident takes away the lives of all his family members. George visits his family's tombs before trying to suicide but feels heartbeats pulsating from Saya's cocoon as if she's telling him to live on. When she emerges from it, George points his gun at her but could not kill her. Rather, she is adopted as his daughter and Saya starts her new life with her dad (George), and adopted brothers Kai and Riku.

Life in Okinawa
In 2005, when Blood+ begins, Saya is a high school girl living in Okinawa who was adopted a year ago by George Miyagusuku after waking from her hibernation cycle with no memory of her identity or past. Though she appears to be a normal teenager, any injuries she sustains heal almost instantly and she must receive regular blood transfusions to remain healthy.

A chiropteran attacks her school and she finds her life turned upside down. She is reunited with her chevalier Hagi, though she doesn't remember him, and learns that her blood can kill the chiropterans. She is approached by David, from the Red Shield, who tells her it is her duty to kill chiropterans because she is the only one who can. Neither David nor Hagi will tell her the truth about her past, telling her she must remember on her own. Though at first Saya is reluctant to fight and afraid of who she might be, she slowly comes to accept her duty and regain her memories.

Back to Vietnam
Working with the Red Shield now, Saya is sent to a girls' boarding school in Vietnam to trace a container. She joins the new school with Hagi disguised as a gardener and conducts nighttime investigation in the backyard garden along the bell tower. In school, she hears a legend of a Phantom who gives blue rose to the girl he's about to take away. Surprisingly she receives the blue rose and also meets the phantom in her nighttime ventures. But she discovers one more thing, something like a container is kept in the cellar. She relates her discovery to David secretly.

A trip to Hanoi brings back memories of Vietnam war. She runs in frenzy and finds herself in an alley cornered by the phantom. A fight is underway and Hagi joins Saya halfway through. When the phantom leaves, he is revealed to be Karl, the headmaster of the school and also a chiropteran.

A grand ball in the school allows Saya to let in her guests: David and Julia. David investigates the whereabouts of the container Saya has mentioned but finds it already moved elsewhere. Meanwhile, Saya catches the eye of the most stunning person of the party: Solomon Goldsmith. He approaches her and asks for a dance and the two of them get along well. An interruption from Van makes Solomon leave and Saya is once again engaged into a battle with Karl. Karl finds out that she is more human than ever and does not remember him. So, he departs from the battle field. As Saya is seen covered in blood and Diva's container is moved, she leaves from the school with David and Julia.

Later, Kai and Riku is kidnapped and Saya goes to rescue them as well as find Diva's container. Once the Red Shield tracks down Diva's container, Saya is paralyzed by hearing Diva singing as she begins to awaken. She eventually reverts to a vicious mindset and goes on a murderous rampage as she did in vietnam war, even mortally wounding Clara, another Red Shield agent. It is in this feral state that Saya fights Karl again, who is overjoyed to fight this Saya. However, she returns to herself again with Kai's help. She once more engages Karl in battle and this time defeats him, though he escapes. She also fails to stop Solomon and Van from safely escaping with Diva on a helicopter.

On the Railway
Saya and her Red Shield fellows board a train in the trans-siberian railroad. There she is met by an imposter who disguises as another fellow agent, Elizabeth. A chiropteran attack on the train knocks out Saya unconscious. She remembers the time she and Hagi visited Russia. When she regains consciousness, she meets Liza and Riku. Later, Liza is revealed to be a chiropteran who refers Saya to go to the Zoo where all her memories begin.

Chasing Diva
After Riku's death, Saya disappears for a year, along with Hagi. When she returns, she has longer hair and a harder, darker appearance. Now accepting of her chiropteran biology, she accepts the necessity of feeding on Hagi's blood to live and be strong enough to fight. However, she has a less cheerful personality, is more morose and less talkative than she used to be. Moses and Lulu both remark that she has lost hope. Believing the fight with Diva is hers alone, and not wanting to have to grieve for any more lost comrades, she avoids cooperating with Kai or the Red Shield. Saya's friends repeatedly work to help her understand that this fight is not for her to bear by herself, and that she is never alone. As the battle with Diva continues, Saya's next hibernation period draws nearer, she starts having sudden bouts of fainting spells, and her regeneration ability slows.

The Final Duel at the Opera
At the Metropolitan Opera House, Saya confronts Diva in a final duel, which ends as they simultaneously pierce each other with their blood-coated swords. Saya is unaffected by Diva's blood, because it lost its potency when she became pregnant. Diva, however, begins to crystallize, and Saya cries for her and tries to hold her shattering pieces together. With Diva dead, Saya turns to kill the babies and herself fearing that if they lived, they would be forced to become military weapons. Kai pleads with her to live, promising to protect her and the babies and make anyone afraid of her understand. Hagi disobeys Saya for the only time in his life, taking her sword and confessing he has loved her from the moment they met. Saya tearfully admits she wishes to live as she kisses Hagi.

Returning Home
A month later, back in Okinawa, Saya finally goes into her next thirty-year hibernation period. At her request, Kai puts her back in the Miyagusuku family crypt to sleep, and he watches over her, and Diva's Children. Several years later, a pink rose with Hagi's blue ribbon is left at the crypt. Hagi is alive and he is watching from afar, waiting patiently for his love to awaken after her thirty year sleep.

Personality
Saya is shown to be spoiled by Joel the first, and is very immature, self-centered, and rude. She herself realizes this as a result of her friendships with Hagi, which helps nurture her compassion for others. However, Saya is a bright, cheerful, and innocent person.

After she unwittingly releases the bloodthirsty Diva upon her foster family and friends and accidentally turns Hagi into her chevalier, coupled with learning the truth about herself, Saya loses her happy demeanor and becomes much more serious and plagued with guilt. She dedicates her life solely to correcting the mistake she made in releasing Diva by killing her, then forever ending the chiropteran threat by killing herself.

As a result of losing her memories and spending a year in Okinawa with new family and friends, Saya develops a sweet personality of an ordinary girl. Kai refers to her as being "a crybaby" and "a glutton". At this time, she is troubled by her amnesia, but only becomes increasingly insecure and worried as she learns more about her true identity and experiences more loss because of the chiropterans.

A year after Riku's death, Saya exhibits a much lonely, self-reserved and darker disposition, having fully regained her memories. In the process, she lost hope, as Moses and Lulu both note. She is unwilling to work with others, particularly Kai and the rest of the Red Shield, not wanting to have to experience losing more loved ones. During the last half of the series, she slowly comes to accept their help. In the last episode, Saya tries to save Diva after having delivered her a fatal wound. She is persuaded from not killing Diva's daughters or herself, leading to her confession that she does want to live.

Abilities
Saya is a skilled athlete and is trained in fencing. She is also taught to play violin and cello when she was in Joel's mansion. In Okinawa, she is seen to be very sportive being a remarkable high-jumper.

Weapon
She fights using a special katana with an edge she can touch with her thumb while gripping it so as to draw blood, and grooves specially designed to spread her blood through its entire blade. Once loaded with her blood, it is a deadly weapon against Diva and any chiropteran created from Diva's blood. After Saya's first blade is broken, David gives her a new one that has a red crystal at the base of its blade, symbolizing her membership in the Red Shield organization. The crystal is a piece of her adoptive father's body, which crystallized when she killed him with her own blood in order to spare him the fate of turning into a chiropteran.