Sona Sitri

Sona Sitri is a High-Class Devil from the Sitri Clan and a third-year student at Kuoh Academy. She is the President of Kuoh Academy's Student Council and a childhood friend and rival of Rias Gremory. Like Rias, she is also the heiress to her clan. Her alias at Kuoh Academy is Souna Shitori, and she is the third most popular girl at the Academy, behind Rias and Akeno.

Appearance
Sona is a young woman around the same age as Rias with black hair styled in a short bob cut and violet eyes. She wears a pair of red glasses and the Kuoh Academy girls' school uniform.

Personality
Throughout the series, Sona is shown to be a very strict type of person. Whether it is a matter of the Student Council or the Sitri Clan, she does not take anything lightly. Sona is very dedicated to her dream of opening a Rating Game School that is open to all regardless of their status, even going to a human school to learn of their system. She also is very protective of her big sister, Serafall Leviathan.

History
Sona is Rias' childhood friend and rival. As a child, Sona had a habit of wanting other people's personal belongings, evidenced by the fact that she would always take Rias' doll when they were younger.

Like Rias, Sona became the heiress of her clan after her sister, Serafall, became a Satan, which resulted in the latter losing the right to inherit the clan. She also had a fiancé, but she broke off their engagement by beating him in a game of chess, claiming that she will not marry someone that is not smarter than her. She entered Kuoh Academy at the same time with Rias, Akeno, Tsubaki, and Kiyome, and later became the Vice-President of the Student Council during her second year.

Birth of the Breast Dragon Emperor
She first appears in Volume 3 along with her peerage, the members of the Student Council, for a meeting with the Occult Research Club to introduce their new members. She then reprimands her new Pawn, Genshirou Saji, for making fun of Issei Hyoudou and nearly challenging him to a fight. She and Rias later found out that Saji and Rias' servants formed an alliance with Xenovia and Irina Shidou to destroy the Excalibur fragments. She then punishes Saji (with 1000 spankings) for acting on his own, and without her permission. When Kokabiel decided to attack Kuoh Academy, Sona and her peerage assisted in forming a barrier to surround the school while maintaining it from outside.

In Volume 4, during the class observation day, Sona's sister came to her school, much to her shock and chagrin. She eventually ran away due to the embarassment caused by her sister. She was also present during the conference of the Three Factions, and was frozen by Gasper's time freezing ability when the Khaos Brigade attacked.

In Volume 5, Sona returns to the Underworld, where she was one of the six chosen young Devils along with Rias, Sairaorg Bael, Diodora Astaroth, Seekvaira Agares, and Zephyrdor Glasya-Labolas. During the opening ceremony, Sona states her dream of opening a school for Rating Game for all Devils regardless of their classes which was made fun of by the elder Devils. She later had a Rating Game against Rias, creating a strategy where she used a hologram of herself as bait while having her two Bishops create a barrier to hide her presence while waiting for the Gremory Team to self-destruct. She almost won the match until Issei, before retiring, reveals his new Bilingual powers to talk with her spirit's breasts to discover her strategy. She then goes to fight Rias in a one-on-one battle, but lost to the latter due to resignation.

The Heroic Oppai Dragon
She faces Seekvaira Agares in a Rating Game (Scramble Flag) in Volume 10, which her team won despite the fact that Saji went berserk near the end of the match. Although the said Rating Game did not get as much of an audience as the Gremory-Bael match, the Sitri-Agares match was highly acclaimed by experts.

In Volume 11, Sona congratulated Issei on his recommendation for promotion for Middle-Class Devil, and after hearing that Issei confessed to Rias, she reveals that she wishes to give Rias as strong as support as possible. She also suggests to Issei that he call her by her first name whenever they are alone since Issei is already Rias' boyfriend which makes him Sona's friend too, but Issei couldn't, and she guesses that Issei receives dissatisfaction from Rias and Akeno regarding how he calls them privately. When Issei questions how she found out, she gave a small laugh, and said that gentlemen who can separate the way they talk to ladies are more wonderful. She also reveals that she is envious of Rias' and Issei's relationship, and starts to think about getting a boyfriend as well. When Issei suggests Saji, Sona rejects the idea since she sees Saji as a brother, and also because some of the members of her peerage are attracted to Saji. Later on, Rias also revealed that Sona has found candidates for her additional Rook and Knight.

In Volume 12, Sona and Saji went to the Gremory Palace to check on Rias and the Gremory Team after hearing about Issei's "death", telling Saji not to get too emotional as she too will be troubled if Saji died and left after telling Yuuto that she called the perfect guy to cheer Rias up. Sona and her peerage later faces off against Heracles and Jeanne from the Hero Faction, losing to them after the two of them used the children of the Underworld as hostages to gain an advantage over the Sitri Group. After Gasper defeats Georg, Sona tells Rias and the Gremory Team that they might face future problems with Magicians.

Power & Abilities
Coming from the Sitri Clan, Sona specializes in using water-based magic and her control over her techniques surpasses that of Rias, as shown during her fight against Rias where she easily controlled a large volume of water. She has also demonstrated the ability to form various creatures out of water, such as multiple hawks that flew in the air, serpents that slithered on the ground, valiant lions, wolves that herded together, and several large Dragons.

Sona's true strength, however, lies in her strategy making. Sona has proven that she is an excellent strategist twice, the first during the Rating Game against the Gremory Team which allowed her team to battle on level with the Gremory Team despite the difference in strength. The second was when the Stray Magicians and Magician from Khaos Brigade attacked the Sitri and Gremory Team, she easily formulated multiple strategies to counter them.

Quotes

 * (To her sister) "Onee-sama, Please be prudent. If my Onee-sama, the Maou glitters, then this small country would be destroyed many times over." (Volume 4, Life 2)

Trivia

 * Sona's height is 166 cm. (5 feet 5 inches) according to the visual book with her data.
 * Sona and Rias share many similarities, in which they are both heiresses to their respective clans, presidents of their respective clubs, their older siblings are both Satans, and they were both previously engaged at one point (Rias during the series, Sona prior to it).
 * In the light novel, Sona appears after Rias broke her engagement with Riser Phenex, while in the anime, Sona appears before Rias broke their engagement.
 * Sona's alias, "Souna Shitori", has the same Romaji as her real name, albeit with minor changes in the stresses in syllables (for example, ソーナ (Sōna) being changed to そうな (Souna) and シトリー (Shitorī) being changed to しとり (Shitori))
 * Sona's breasts had a voice similar to her sister, Serafall, (down to using stars in place of periods) when Issei first used his Bilingual ability on her and her peerage during a Rating match at the Young Devils Gathering.
 * Sona is known as one of the "Rookies Four" along with Rias, Sairaorg, and Seekvaira.