Esther Rosenthal

Esther Rosenthal (エステル＝ローゼンタール) is a magician who first appears in Toaru Kagaku no Accelerator.

Etymology
was a biblical figure and the main character in the, part of the Jewish and the Christian Old Testament. A Jewish orphan who became the new wife of the Persian king, she asked the king to rescind an order to kill all the Jews in the kingdom (after the vizier was offended by her cousin and guardian  not bowing) and won permission for them to kill their enemies.

is a surname of German and Ashkenazi Jewish origin, meaning "valley of roses".

Appearance
Esther is rather well-endowed and has blonde hair and green eyes. She has a mole under her left eye. She wears a black cloak over a sleeveless white blouse, which is open on the back, with a red skirt under a large belt. She wears two black ribbons on her temples. Her forearms are covered in bandages and she wears gloves. She wears black thigh-high socks, her legs have leather straps, and her ankles are bound with metal rings. She wears dark underwear.

After her clothes got wet shortly after meeting Accelerator, she wore a nurse's uniform during the incident which followed, initially wearing her cape over it before giving it to the Huotou, possessing the corpse of Hitokawa Hasami, to cover up its host's body.

Personality
Esther is shown to be generally kind and polite to people. She values humans and life,        and shows respect for the dead,    being angered when they are disregarded and exploited in despicable fashions. Even though they are dead, Esther recognizes that the corpses she animates are not just dead bodies but those of people and does not see them as expendable, preferring that no harm or indignity come to them.

While she didn't fully understand at the time she first entered Academy City,  as a result of losing her friend Hirumi twice (first through her death and then her own attempt to revive her), Esther understands the weight of life and death, and that one should not toy with death. Having shared her knowledge of necromancy without grasping the full consequences, something she deeply regrets, Esther holds herself responsible for the atrocities which Hishigata and DA committed with it, and was determined to stop them, as well as the one behind them, from toying with life and death any further, even if it cost her own life. Abandoning the long-held desire of the Rosenthal Family, Esther intended to abandon necromancy altogether once she had stopped the ones abusing their techniques.

Esther has been shown to be unfamiliar with certain aspects of modern life. A meal at a family restaurant was a new sensation to her, which she found delicious, unlike anything she eaten before, and attributed to Academy City's science. She was also startled when using a shower. She is unbothered with being in a state of undress in front of others,  as seen when Accelerator walked in on her while she was just in her underwear, much to Last Order's chagrin, and she was confused as to why she should mind.

Having seen Accelerator save her and others with ease, she holds him in high regard, even asking him to become her teacher and referring to him as such.

In the anime, she used to refer to herself in the third-person.

Background
Esther is the current head of the Rosenthal Family, who have spent 400 years and 23 generations developing necromantic techniques in order to create the perfect golem, one with a perfect soul and perfect body - a god. She was raised and trained in the family's style of necromancy to pursue this goal (and warned against careless teaching it to others), though she did not fully understand the meaning and weight of life and death. She also inherited the family's tools, including the powerful and dangerous artificial souls known as the Evil Spirits of the Numbers.

At some point within the past five years, Esther came to Academy City and was apparently tricked into joining Hishigata Mikihiko's research team as a supervisor, to aid in their research on where esper abilities originated from in the human body and later strengthening esper powers by reinforcing the physical body. Despite the nature of this research (and the supposed deception), Esther shared her knowledge of necromancy without fully grasping the consequences, enabling them to make considerable progress, though only with corpses, eventually leading to the creation of the Coffins. During this time, she also became friends with Hishigata's younger sister, Hirumi.

However, at some point in early August of the current year, Hirumi ended up dying under unknown circumstances and seeing her friend dead in front of her, Esther tried to revive her using Taowu, one of the Evil Spirits of the Numbers. While Hirumi's dead body was reanimated, she was not brought back to life. Additionally, unknown to Esther, the Taowu contained the will of her ancestor Isaac and on activation, it was secretly contacted by a self-proclaimed demon who conveyed a method to achieve the goal of the Rosenthal Family by using the memories of 10,000 deaths to bring an artificial soul to Keter. Influenced by Isaac's desire to achieve this goal, the Taowu prioritized and moved to accomplish the plan, disregarding Esther's orders, posing as Hirumi and manipulating her brother to carry out the plan under the guise of making her into a Level 6.

Esther soon realized that she had lost control of the Taowu and that whatever will was guiding it planned to interfere with the processes of life, death and reincarnation, potentially altering the world at a fundamental level. As a result of losing her friend twice, Esther came to understand the weight of life and death, and realizing that they should not toy with death, she abandoned the desire of the Rosenthal Family. Following this change of heart, she ended up being held captive while Hishigata continued to develop the Coffins using the techniques she'd taught him, even using the other Evil Spirits of the Numbers, along with the resources of DA, whom he shared the technology with. She eventually escaped and sought out Last Order, having learned that she would be targeted to obtain the memories necessary for the plan from the Misaka Network.

Necromancer Arc
Esther first appears while being pursued by DA. While escaping them, she enters a certain hospital and finds herself in Accelerator's room. She attempts to ask him about Last Order, however Accelerator doesn't notice her due to using his power to deflect sound away from him while reading. While she tries to get his attention, her pursuer catch up with her and manage to subdue her. She is later tied up with several belts and gagged. Despite her bonds, she manages to get out during the scuffle between the Anti-Skill and Accelerator who has come to take her away for questioning as she carried a photo of Last Order.

She escapes her restraints during Accelerator's battle with Nishio and the prototype Coffin, and later reappears before Accelerator, in his room, inquiring about the girl on the photo, Last Order.

After a rocky start with Accelerator, she tells him of DA and their plans and later bring him to the warehouse where she was restrained. There, they discover a huge mecha, a Coffin known as the Qiong Qi, and find out that DA's plans are already in motion. Later, Esther performs a magic ritual on Hitokawa Hasami's corpse, in order to put her to rest. While doing so, the curious Accelerator touches the physical form of Hasami's residual memory, allowing him to see how she had died. Esther sucessfully possesses Hasami with her Huotou and closes her spiritual circuit but is interrupted by the arrival of DA operatives who have come to dispose of the body. As a result, the Huotou activates and takes control of Hasami's body allowing her to fight for Esther as she is her master.

When Accelerator stumbled after dispatching the first DA member, Esther asked if he was OK and noticed his head bleeding due to his wounds reopening. As the second DA member tried to escape, Esther attempted to pursue him but he used his blade to bring the ceiling down on top of her, though the Huotou protected her using Hasami's body. Seeing her path was blocked, Esther looked for another way, which the Huotou found. After the Huotou told her to hang on, Esther gave it her cloak to cover Hasami's naked body. It then carried her after their quarry, breaking through a wall and intercepting the DA member as he was escaping the hospital.

Toaru Idol no Accelerator-sama
Esther debuts in chapter 6 of the 4koma gag manga alongside Hitokawa Hasami. After Hasami dies after being awestruck by Accelerator's wings, Esther accidentally inserts an artificial soul into her and becomes Hasami's master. From then on, Esther is shown as an unabashed fan of the idol Accelerator being accompanied by her servant Hasami.

Abilities
Esther is a necromancer,   and as such specializes in magic involving the manipulation of the dead. She uses a method of inserting artificial souls into corpses to animate them to do her bidding. Although she is capable of defending herself with her dagger and knows a number of non-necromantic spells,    she primarily relies on her reanimated servants in battle. The majority of Esther's spells utilize paper charms with magic circles inscribed on them,       which often expand additional magic circles when she uses them.

Rosenthal-style Necromancy
As the 23rd head of the Rosenthal Family, Esther is trained in and proficient with Rosenthal-style Necromancy. It is a mixed style with an initial foundation based on Kabbalah, having originally developed from heretical golem research, combined with elements from Taoism, such as the Hopping Zombie Spell,  and centered around a method of manipulating dead bodies by inserting artificial souls into them. Unlike traditional golems, which are typically rock or mud dolls only capable of following simple commands, this technique utilizes the human brain in order to create a more intelligent servant.

When implanting an artificial soul into a dead body, Esther first places the charm containing it onto the corpse. She then "reactivates" the body and calls in the wandering residual information. At the same time, as seen in the case of Hitokawa Hasami, a magic circle is formed on the floor around corpse and necromancer, accompanied by additional light around the charm's contact point. The deceased's "residual thoughts" (残留思念) are used as a key code in order to slip the artificial soul into the body.

While gathering the residual thoughts to use as a key, the residual memory takes form outside of the corpse in the shape of a floating brain. If someone touches it, as in the case of Accelerator with Hitokawa Hasami, the memories of the deceased flood into that person's mind. If not controlled, the residual thoughts can take a dangerous form which people sometimes call ghosts (specifically jibakurei (地縛霊)). Once the artificial soul has been successfully connected, the charm disappears into the body and Esther can then manipulate the corpse, either having the soul animate it or carrying out a different task.

Although the method is primarily used with human corpses, it is possible to use it on the corpses of other animals, though without a human brain it won't display the same level of intelligence.

In addition to animating corpses, Esther can also use the artificial souls to close a corpse's open spiritual circuit (such as in the case of Hitokawa Hasami after an earlier misuse of necromancy, which might have resulted in the corpse crawling back even if buried and might prevent the deceased from passing through the gates of Heaven) and perform a ritual to properly lay the dead to rest.

Artificial Souls
The artificial souls at the core of Rosenthal-style Necromancy, also referred to as false souls (偽りの魄) or pseudo-souls (疑似魂魄), are formed through an application of the Sephiroth and stored on paper charms with magic circles and symbols written on them. When summoned, the soul is bound to follow the orders of the head of the Rosenthal family. All of the known artificial souls used by the Rosenthals have names based on ancient Chinese figures, due to the family's history in the East and the influence of Taoism in their spells.

Esther has had a number of artificial souls at her disposal, with both high and low level spiritual charms. Huotou is an artificial soul which she personally created. As the 23rd head of the Rosenthal Family, Esther inherited a set of four powerful and dangerous artificial souls created by 5th head Nathan, known as the Evil Spirits of the Numbers (ナンバーズの悪霊) and bearing the names of the Si-Xiong (四凶) of Chinese ; Taowu, Taotie, Hundun and Qiong Qi. Difficult even for necromancers to control, they could enhance the abilities of the corpses they possess to levels greatly exceeding the body's potential.

Esther used Taowu in her attempt to revive Hirumi, but lost control to the will of Isaac imprinted on it, unknown to her. During her captivity, the other three were taken and used in Coffins, enhancing the esper abilities of their corpses to Level 5-class. The Coffins were eventually destroyed, while Taowu's charm was pierced by Emperor Shun's Blade.

Huotou
Huotou (禍斗), also referred to as the Rosenthal Third Number (薔薇渓谷家参式 (ローゼンタール サードナンバー) ), is the main artificial soul used by Esther during her time with Accelerator, possessing the body of Hitokawa Hasami after her death. Originally implanted into her body in order to close her open spiritual circuit and lay her to rest properly, the interruption caused by DA led to the artificial soul automatically activating and animating the corpse,   serving as Esther's protector from that point onwards.

Huotou speaks in a robotic manner and addresses Esther as Adonai (ご主人様 (アドナイ) ). Obeying Esther's commands, it accompanies its master and acts automatically in order to protect her. If it is in danger of being destroyed, it will prioritize protecting its charm, allowing damage to the corpse if necessary.

While using Hitokawa Hasami's body, Huotou displayed increased strength and speed greater than that of a normal human, being capable of breaking a man's arm and weapon with a single kick, leaving a crater in the floor. It is capable of increasing them to even greater levels at the cost of damaging its host body. By allocating 60% of its host brain's capabilities, it can also temporarily increase the host's sense of smell in order to track scents. It isn't known if Huotou can use Hitokawa's Pyrokinesis.

Armor of the Dead
The Armor of the Dead (死者の鎧) is an armor made from dirt, produced to protect and bolster animated corpses.

To activate the spell, Esther places one of her paper charms on the ground at a point were there is a sufficient amount of soil on the surface, producing a magic circle, and invoking a Gnome (土精</rb> (</rp>グノーム</rt>) </rp>). This gathers dirt around the corpse and forms it into an armor of earth which shields it from harm. In addition to increasing their defenses, it can form pieces of armor around the corpse's limbs to increase their attack power.

Additional dirt can be supplied to repair the armor, but the user must apparently remain in place and continue invoking the spell to provide it.

Emperor Shun's Blade
Esther possesses a dagger known as Emperor Shun's Blade (舜帝の剣), a countermeasure against the Rosenthals' artificial souls. It has a double-edged blade as wide as its hilt, dark-colored on its side with a red diamond pattern (which glows when the blade's spell is prepared), decreasing towards and before the tip. It is stored in a sheath on the back of Esther's waist belt.

As well as being wielded as a regular dagger, it is used for a neutralizing spell known as Spell of Emperor Shun's Blade (舜帝の剣の術). The dagger is prepared by placing it in the center of a carved magic circle, tip down,  and performing an incantation. Once the preparations are complete, the dagger can neutralize the artificial souls used by the Rosenthal family on touching their charm, separating them from their hosts, and is described by Esther as poison to the likes of the Taowu.

Other
Aside from her necromancy, Esther has a number of other spells which she can perform using paper charms, sometimes coupled with incantations or gestures:

Some of them produce magic circles at the charm's position (either placed on the ground or thrown through the air), which can safely launch people standing on them upward (surrounded by a green glow while airborne) or act as a mid-air platform for people to jump on and off.

Another charm allows Esther to sense the locations of nearby artificial soul charms, such as that of Taowu. At least one type of charm allows her to monitor the circulation of life force through a living individual, though she doesn't possess healing magic and can only perform basic first aid.

In the anime adaptation, she demonstrates a proficiency in close combat when fighting DA goons at Heaven Canceller's Hospital.