Sena Aoi

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Sena Aoi
Name
Japanese	蒼井 セナ
Rōmaji	Aoi Sena
Aliases	Previous name: Sena Hatano (波多野 セナ, Hatano Sena; her father's surname) Nicknames: Girl B (by Takumi) Sena-shan (by Kozue)
Characteristics
Gender	Female
Age	17
Birthdate	March 8, 1991/1992
Height	162 cm (5'4")
Weight	46 kg (101 lbs)
Measurements	B75/W54/H79
Blood Type	AB
Personal Status
Status	Alive
Affiliations	Suimei Academy Ark Heart Medical (before) Gigalomaniacs
Occupations	Suimei Academy Third Year Student - Class A
Relatives	Issei Hatano (father) Unnamed mother Mana (little sister)
First Appearance
Visual Novel	Chapter 1
Anime	Episode 3
Manga	Chapter 4
Voice Actors
Japanese	Hitomi Nabatame
English	Clarine Harp

“	...Is the scenery your eyes perceive truly real?	”
	— Sena Aoi, Chapter 4

Sena Aoi (蒼井 セナ, Aoi Sena) is a senior at Suimei Academy and a Gigalomaniac who goes around in public with her DI-sword.

Appearance

Sena has waist-length silky dark purple hair (black canonically) flowing freely past her waist and a serious, confident expression that matches her assertive demeanor, and almond-shaped purplish eyes.

She is usually seen in her school uniform, wearing a cream-colored blazer with red trim along the edges, and it features a school emblem on the left chest. Under the blazer she has a white button-up shirt, slightly unbuttoned at the top, and she wears a loosely tied dark plaid necktie that matches her skirt. Her skirt is a pleated design in a purple and navy plaid pattern, short in length, with a frilly white lace lining peeking out from the hem. On the rare instances when she is not seen in her uniform, she wears a white summer dress with a black ribbon tied around her waist.

She is often seen with her DI-sword or eating a blue popsicle. While she is attractive, she is also very intimidating and almost always has a stern look.

Personality

Sena is an overall skeptical person who often acts hostile, unfriendly and aggressive, and tries to put on a tough girl act. She hates her father with a passion and wants to track him down to kill him.

Sena is a firm believer in everything having a scientific explanation and has gained much of her knowledge from her father. Having a very logic-oriented mindset, she attempts to use reasoning, especially in stressful situations, but is disposed to go overboard to the point of becoming paranoid and ignoring critical advice. She feels tremendous guilt over having felt repulsed by her sister Mana's corpse and her mother's suicide, a feeling she sought to push away by solely focusing on despising her father and blaming him for their deaths. In the Sena route, she admits that she had only begun thinking of the world as digital, or, in her words, “an eletronic device“, to eliminate her own emotions.

Despite her dominant worldview of a digital world, throughout ChäoS;HEAd she immediately grows hostile when others point out the contradiction between her own mindset and her feelings — namely, that she would be furious at her father at all. Since, if the world truly were entirely digital, then Sena's feelings would only be part of that digital code, thus having no real substance. This suggests that her feelings and supposed logical mindset had been disconnected from the start.

It later turns out that, while Sena despises her father Issei Hatano, she seemingly still cares for him as a father. For example, when sleep talking she calls him "dad" while crying, instead of like usual by his last name. At his death in some of the routes, she also weeps for him. In the Crying Sky ending (or B ending in the original ChäoS;HEAd), when she finally, although accidentally, kills her father, even though it had been her plan since the very beginning she suddenly finds herself in a severe state of shock and becomes unstable.

DI-Sword

Sena Aoi's DI-Sword has a futuristic and sleek design. Her DI-Sword is named "Gladiolus", after the flower which means strength, moral integrity, and remembrance. This exactly fits for Sena's personality as she is a determined and fierce girl with goals and wont stop at nothing. The sword has a double-edged split-blade design, with two long, sharp, crystal-like edges that run parallel, resembling high-tech twin beams. The split gives it a distinctive and aggressive look. It predominantly features a shimmering icy-blue and silver coloration, giving it an ethereal, almost holographic quality. The light reflections suggest a crystalline or energy-based material. The hilt is compact and sharply angled, with a uniquely curved guard that resembles futuristic armor or wings. The guard has a layered, aerodynamic form that enhances the sword's sleek and modern aesthetic.

Background

When she was fifteen, her mother was about to give birth. Her father, the scientist Issei Hatano, decided to volunteer his wife for the Mana Experiment and sent Sena to live in the psychiatric hospital Ark Heart Medical. With the help of a device capable of deluding its wearer, the Noah II prototype, what his wife saw was her happy newborn child, Mana, and a pleasant daily life that she thought was given her by her husband’s company, N.O.Z.O.M.I. She lived alone with the baby, as she had been told that her husband had moved for his job along with their elder daughter. She was assisted in her life by a “neighbor” and a “housemaid” who looked after her, and made it possible for her to stay inside all the time with her baby. She and Mana were very attached, and they spent all their time together.

Sena discovering the truth about her mother.

Two years passed, and the end of the experiment drew near. The scientist begged for it to be continued so as to not have her mind broken by the truth, but N.O.Z.O.M.I. already had all the data they needed and had therefore no need for a continuation. The reality of what had taken place over the last two years weighed heavily on his heart. Just one month after Mana’s birth, she died suddenly. Issei had initially tried to stop the experiment, but the company had thought of this as the perfect conditions to test Noah II. Sena’s mother looked after the corpse of her daughter for two years, thinking she was still alive.

When they turned off Noah II in the May of 2008/2009, Sena's mother saw that Mana had been mummified, and the stench from her was overwhelming. As she looked at Mana, her heart broke. She devoured Mana, and then began banging her head into the wall before digging out her eyes. Finally, she stabbed a kitchen knife in her eyes and died, all of which Sena witnessed from behind glass. Sena screamed in shock and despair and vomited out of disgust. Following that, she ran away from Ark Heart Medical, changed her surname from Hatano (波多野) to her mother's maiden name, Aoi (蒼井), and proceeded to hunt her father down in the months that followed to enact revenge.

Plot

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Quotes

• "Ignorance is a sin. People claim 'ignorance is bliss', but that's simply naive. Doubt the world. Study its mechanisms. This world is imperfect. ...Is the scenery your eyes perceive truly real?" — Sena's warning to Takumi Nishijou.

Trivia

• Sena likes science and “Crunchy-kun” popsicles (「ガルガリ君」, “Garugari-kun”; a certain brand of ice popsicles), but dislikes and is afraid of dogs.
• Sena's birthstone is the aquamarine.
• During her spare time, Sena likes reading in bookstores.

Etymology

• Sena’s surname Aoi means “blue, pale” (蒼, ao) and “well, well crib, town, community” (井, i).
• Sena’s previous surname Hatano means “waves, billows, Poland” (波, ha), “many, frequent, much” (多, ta) and “plains, field, rustic, civilian life” (野, no).

Gallery

Showing her DI-sword.

Destroying the backpack of a porter.

Commemorative group photo of Sena, Takumi Nishijou and Kozue Orihara.

Shoving her foot at Takumi Nishijou's face in a positive delusion.

Rimi deflecting Sena's strike.

Trapped under rubble in N.O.Z.O.M.I. building in her route.

Holding the "cheat code" in her route.

Graphic from Sena's official birthday post in 2023.