Saya's sister

Diva (ディーヴァ Dīva), is Saya's younger twin sister and the main series antagonist. She is the greatest sworn enemy of the Red Shield.

Appearance
Diva has similar features to Saya only she's a little fairer and perhaps more beautiful than her sister. Ted A. Adams, the farmer near zoo both acclaims that she's the most beautiful and dangerous woman. She keeps her hair long most of the anime. Only during shape shifting to match Riku's appearance, she shortens her hair. She has glowing blue eyes.

Attire
The main antagonist, Diva, having five wealthy chevaliers at her disposal, showcases several attires throughout the series:
 * White long dress with blue ribbon across the waist
 * Midnight blue gown with grey ribbon across waistline
 * White taffeta dress with frills and blue bordered fringes
 * White top and blue scarf with a blue rose; black shorts and shoes.
 * Dark blue dress with black bat-wings and a collar with blue rose and white ribbons.

Birth
In 1833, Saya - The Mummy of an unknown creature was brought to the zoo at Bordeaux, France. Dissecting it revealed that it was pregnant and had two cocoons which were discovered by Joel Goldschmidt and Amshel. The cocoons reacted to human blood. Diva was born in 1833 from one of these two cocoons.

Life in the Zoo
Joel separated the twin girls, as an experiment, raising Saya as if she were his own daughter while Diva, who was given no name, was locked in a tower and given only the basic necessities to live by Joel's assistant, Amshel. She was experimented on rather ruthlessly which is proved when Joel tests on their blood, procuring a bowl from Diva while taking only a few drops from Saya.

On a certain day in 1863, Saya went walking and heard a beautiful singing voice. She came across the girl imprisoned in the tower following her song. She asked the girl to be her friend. Saya asked what her name was and she said she didn't have a name. Hearing her wonderful voice, Saya named her Diva.

Twenty years later, in 1883, Diva was released by Saya from her tower so that she can sing at Joel's birthday party. However, Diva murdered Joel along with the rest of the people attending the party before fleeing the area. It is likely that she turned Amshel into her chevalier then.

Appearance at Intervals
Diva is hunted by Saya from then on but manages to flee from her sister with the help of her chevaliers. She was shown when Saya came around in the Russian village. Gregory held off Saya just long enough for Diva to escape with Amshel.

She awakens during world war I in the presence of Amshel who brought Solomon. She made him her second chevalier and before going to sleep, she also made Karl her chevalier.

During the Vietnam war, it is yet unsure if she actually appeared. But her voice was heard by Saya who followed the song and entered a village to carry on her slaughter party.

Awakening
By 2005, Diva wakes up in Vietnam where she has been hibernating inside a container within the Lycee grounds. She is taken to Paris in Solomon's mansion. By that time, she has five living chevaliers, who head up the Cinque Flèches Group.



Meeting Her Mate
Amshel takes Diva to the Zoo and she returns to her cell, singing once more. Her voice attracts Riku who is drawn to the place. After meeting Riku at the Zoo, she drinks most of his blood. When Saya arrives there the two sisters break into a fight. Saya is no match for Diva's savage strength but interventions from both Red Shield and Solomon as well as Diva being unwilling to play anymore draws temporary pause. As Diva goes away with Solomon, Kai pleads Saya to save Riku with her blood ; resulting in forcing Saya to turn him into a chevalier in order to save his life.

Diva becomes increasingly interested in Riku after the incident. Eventually she infiltrates the Red Shield headquarters with Karl to find him. She follows his heartbeats and finds him despite Kai's efforts to hide his brother. She rapes Riku, and gives him her blood which crystallizes him.

Becoming a Mother and Pursuing Dreams
As a result of her attack on Riku, Diva becomes pregnant. She does not give birth for over a year, when Amshel cuts the cocoons out of her body. Diva seems to treasure her babies and caring for the cocoons. A year after this attack, when the Red Shield manages to regroup, Diva changes her physical appearance to resemble Riku and retains that appearance until her final battle with Saya.

Diva becomes an opera singer in New York, sponsored by the Group. Cinq Flèches spreads the Delta 67 agent, which could turn people into chiropterans, across various populations of the world, including the United States. When heard live, Diva's voice greatly increases the effectiveness of the agent.

Final Duel at the Opera and Death
At the Metropolitan Opera House, Diva is set to perform a live broadcast which would cause a large portion of the world's population to turn into chiropterans. The Red Shield and Saya manage to stop the broadcast although they couldn't get to Diva in time to stop her live performance.

The sisters have their final battle while Diva's chevalier Nathan watches nearby with the babies. The fight ends as Diva and Saya pierce one another with their swords, which each had coated with their own blood. Saya is unharmed by the attack due to Diva's blood having lost its power when she became pregnant. Diva begins to crystallize from the effects of Saya's blood. Nathan leaves the cocoons beside her and Diva reaches for them; imagining herself with her daughters and smiling at the vision before dying.

Her Chevaliers
Following is the list of names of Diva's chevaliers according to the sequence they were made into her chevaliers:
 * Amshel Goldsmith
 * Grigory
 * Martin Bormann
 * Solomon Goldsmith
 * Karl Fei-ong
 * James Ironside

Personality
Diva, unlike her sister Saya, was locked in a tower and tested on, while Saya was sent to live with the humans to be observed. Diva began to hate humans, while Saya loved to live with humans. At the end of the series it was shown that all Diva wanted was to live with her loved ones, her family.

Due to her upbringing, Diva has a ruthless nature wrapped in an often child-like demeanor. She giggles after killing people, shows little reaction to the death of her own chevaliers, and tends to destroy things when bored. Diva seems to enjoy tormenting Saya and frequently shows the desire to kill her.

Saya
Her relation with her elder sister is complicated. She addresses Saya as "big sister". It is never showed if she actually hated her despite the cat and mouse game between them. Diva envies Saya having a family of her own; something that she never had. She likes to torment Saya and wishes to kill her. Even after getting several occasion where she could pretty much finish off her sister, she simply leaves under the pretense of being bored. On the final duel, she had the intention for both of them to die. But tragically her blood had no effect on Saya as it had long lost its power.

Joel I
Diva hates Joel I for locking her up all those years and experimenting on her mercilessly. So, the moment she realizes that Saya has freed her, she lets out all her vicious emotions and causes the bloody massacre. She rejoices in draining Joel's blood and Saya catches a glimpse while she was doing so.

Amshel
While locked up in the tower, Amshel was her only company. She listens to Amshel among all her chevaliers. To her, he is sort of a father figure although all Amshel ever wants of Diva is to be his experimental subject.

Nathan
Diva gets all the opportunities to perform on stage via Nathan. She isn't shown to be much interactive with him. Once she drank his blood despite his vain efforts to stop her.

Solomon
Out of all her chevaliers, Diva favored Solomon. She liked to cling on to him and stayed at his place for quite a long time after her awakening. After he betrayed her to join Saya, she disowned him and ironically suggested him to mate with Saya. When he came back to attack her children, she beat him up leaving him badly wounded.

Karl
Diva gave the least attention to Karl which is why he always seeked a way to gain favor. He even kept her mad requirements and took her to the headquarters of Red Shield. Lastly Karl became obsessed with killing Saya. When he died in the process, the news of his death was given little importance by Diva.

James
Diva called James 'my child' and he called her 'mother'. James remained loyal to his mother Diva and she cared for him too. But after his body parts were replaced with that of schiffs, Diva approved of him no more.

Riku
Since the time Diva first met Riku at the zoo, she felt a maddening attraction towards him. She referred to him continuously as 'the boy'. When she reached the Red Shield HQ, she listened to his heartbeats and followed them to find him. There she rapes him (her way of playing) and gives him her blood (thanksgiving gift!).

Her Daughters
Diva cared most about her babies. Like a good mother, she kept them from all harms. In her dream, it is shown that she's with her babies in a green field where she is singing to them as they are playing. But her dream never comes true as she dies caressing the unborn cocoons.

Kai
After Riku's death, Diva wanted to make Kai her chevalier. She places his hand on her abdomen where the babies are – her and Riku’s babies. She dedicates her performance to Kai. She tries to show reasons why he should be with her: protecting her and Riku's babies and even making children with Saya once he becomes her chevalier. Kai pulls out and points his gun at Diva. She puts her hand on it and tells him that by squeezing the trigger and drinking her blood, he can be together with her. She makes her final plea in Riku’s voice but Kai's better judgement takes control.



Skills
Singing: Diva was a born singer and she was named after this talent by Saya who heard her sing and henceforth called her 'the singing Diva'. Only Nathan wanted Diva to continue performing and become a star while Amshel wished to use the skill to create more chiropteran.

Sword-fighting: Although she has not received training to fence like Saya, she has shown quite flexible movements wielding longsword during the final battle.

Exceptional Abilities
Strength: Diva shows ultimate strength and is the strongest of all characters. Even a chevalier is likely to face mortal wounds if she strikes any. It is affirmed by Nathan when he sees Diva beat up Solomon for daring to try hurt herself and her children.

Speed: Diva shows to be highly agile. Her speed stirs up fear as shown when she attacked Red Shield HQ.

Flight: Diva can perform long distance jump similar to flight if considered the way Saya jumps. She rarely uses it since she likes to rely on her chevaliers to take her wherever she wants.

Telepathy: Diva shows this ability communicating with chevaliers if necessary. But mostly she uses it to find Riku on Red Shield ship. She listens to his heartbeat and follows it.

Voice: Her mesmerizing voice was not only a sheer talent but also a power that controls, awakens and attracts chiropterans. Her voice also intrigues Saya and drives her to frenzy, awakening her to chiropteran mode.

Blood Attributes:
 * Regeneration: Diva has the usual ability to heal herself from any normal injuries.
 * Anti-aging: Her special blood stops her growth after aging 16 years, the same as her sister Saya. That was why she looks the same even after originally surpassing 173+ years!
 * Crystalization: When mixed with Saya's blood, Diva's blood crystallizes. This is lethal to her. In turn, her blood can crystallize Saya and her chevaliers. She didn't know that Riku was Saya's chevalier and gave him her blood as a return gift for being impregnated, thus bringing about his death.
 * Conceiving: Queens lose their blood powers when they conceive. Diva, having forcefully mated with Riku, unknowingly loses her power to kill her sister. This was known to Nathan only and he explains it to Saya when Diva dies. On her final duel with Saya, she plunges her sword loaded with her blood into Saya and simultaneously gets impaled by Saya. But only Diva begins to crystallize and dies.