Yumiya Iruka

Yumiya Iruka (弓箭入鹿) is a student of Tokiwadai Middle School as well as a member of the archery club, who appears in Toaru Kagaku no Railgun: Astral Buddy.

Etymology
Like Yumiya Rakko, her family name "Yumiya" (弓箭) literally means "bow and arrow", an apt name for someone who knows archery. Her given name "Iruka" (入鹿) can be interpreted as "dolphin".

Appearance
She has long wavy hair, which she ties with a ribbon at the back. Her fringes cover the right side of her face, and she also wears a traditional Japanese hair ornament, the. As she is a member of the archery club, she wears the traditional garb for it. When wearing her Tokiwadai uniform, she wears stockings instead of stocks.

The fringes that cover the right side of her face are so she can hide her scar and right eye which has a prism inside it, which she can use in conjunction with her powers. According to Junko's analysis, the way she looks including her decoration is to force people's attention away from the right side of her face.

Personality
As an ojou of Tokiwadai, she has a serious and refined personality to her, and is approachable by the other girls. As caretaker of her older sister, she is skilled at taking care of others, though she shows excessive kinship. She has a habit of subconsciously kissing the other person.

However, she carries a dark side as she is able to successfully plan and take down Shokuhou Misaki. Though she prefers to take an advisory position, using trickery to defeat an opponent, she is willing to battle herself if needs be.

Iruka looks up to Junko and wants to surpass her but is disappointed by her holding herself back. Her failure to become a Level in Ideal drove further into this way of thinking. Much of her actions in the Astral Buddy arc are done to force Junko to stop holding back and show how she wasn't wrong in looking up to her. She will not hesitate to sacrifice her own life in the process.

She is also a secret fan of Gekota, thanks in part to Junko's influence.

Later a more light hearted/comedic side to Iruka's personality is seen during her time reunited with Junko,as seen when she would blush heavily when Junko would give her attention and later enter into a comedic-friendly argument with her over Junko's past antics, showing that her friendship with her has more or less been mended. Iruka has also shown a level of annoyance/jealousy/rivalry with Shokuhou Misaki over Junko's attention and is seen jealousy glaring at her during her and Junko's time recovering in the hospital after their duel due to Shokuhou's habits of teasing people and her own actions of purposefully showing off her close relationship with Junko to Iruka's face and her later claiming that Junko belonged to her, causing her to then comedically get angry at Shokuhou due to her antics.

Background
She was part of Clone Dolly, a workshop created to make geniuses. One day, she and her older sister, Rakko, visited the Third Laboratory: Ideal, where they met Mitsuari Ayu and later Hokaze Junko. Iruka tried to approach her, but was told by Junko not to come close as she was a danger to others. Suddenly, Junko got a headache and she staggered next to the wall, cracking it. Ayu informed her that Junko became a Level 4 from a Level 2 in only two months, and Junko later proved her power by destroying a punching machine. Iruka was impressed by this, and Ayu told her that everyone admires Junko and the facility is meant to raise a Level 5. Hearing this, Iruka thought that she can be like Junko as well. From then on, Iruka's powers became more developed, while Ayu plateaued and Rakko remained a Level 0. However, despite her dream of surpassing Junko, neither of them actually became a Level 5. Later on, Iruka would discover that Ideal never meant to turn them into Level 5s and found that she had no talent in becoming one no matter how hard she worked for it. It would later be revealed that it was because that the true Level 5 powers development is only being given to one girl: Shokuhou Misaki.

Iruka later enrolled into Tokiwadai, the same school where Junko goes to.

Astral Buddy Arc
After being introduced by a teacher, Iruka teaches Kuroko and Junko archery. The teacher decides to turn the session to a contest between the girls where the winner gets a rare Gekota makeup poach, of which there is believed to be four prototype versions. During the contest Kuroko misses the bullseye and due to Iruka secretly interfering with Wave Conductor, Junko also misses her target, leaving Iruka the winner. Iruka wishes that Junko had taken it more seriously.

Afterwards, Misaki is incapacitated by a trap that Iruka had previously set up. Iruka and an accomplice approach. Iruka rejoices over the success of their plan, only to be caught by surprise by Makigami Komaki and tied up. Iruka's accomplice defeats Komaki, but is delayed long enough for Junko to arrive. Junko fights the accomplice, and during this fight Iruka is overjoyed at Junko's arrival but dissatisfied that she still isn't fighting seriously. Iruka breaks out of her restraints and threatens to attack Komaki, tricking Junko into saving her and hence being caught in a net trap. Iruka and her accomplice leave with Misaki, Iruka telling Junko to follow them but to do so alone.

Iruka and her accomplice flee in a truck, keeping Misaki in the back. They are unaware of Misaki being possessed by the ghost girl. They investigate the back of the truck after hearing a noise (the ghost knocking over a box of Indian Poker cards), but attribute it to the box falling over from the truck's movements, as the ghost has Misaki lie down and pretend to be unconscious. Iruka criticises her accomplice for not paying attention to her appearance. She then touches Misaki, apologises for dragging her into this and promising to free her afterwards, then kisses her on the cheek.

Iruka realises that Junko is tracking them via Misaki's phone. She takes the phone with her to lure Junko to an abandoned warehouse. The two of them talk, but Iruka refuses to explain the reason for her actions, and they begin fighting. Iruka manages to force Junko to retreat, but collapses in exhaustion and eats a glucose pill. She searches for Junko and finds an improvised bomb, which detonates and ruptures the roof's water storage tank. The resulting water hinders most of Iruka's attacks. Iruka tries one last attack but is still knocked down by Junko's attack. Iruka still refuses to give up as Junko has yet to use her true power. After explaining herself, Iruka unleashes a barrage of lasers from her prism eye. However, even this fails as Junko blocks the lasers with her body. Iruka faints, satisfied with Junko's power, and Junko catches her to prevent her hitting her head on the floor.

Abilities
Iruka's ability is Wave Conductor (波動操作 (ウェイブコンダクター) ), which allows her to control waves of light and sound, or "anything with the properties of a wave", amplifying and concentrating them. Through this, a twang of a bowstring can be amplified to startle someone, and a flash of light can be amplified knock someone out. Her powers are more easily focused and amplified when she is holding the waves source.

However, Iruka primarily uses her powers through a simple laser pointer and military flashlight, though not at the same time. Using her powers, she amplifies her laser pointer into an actual laser capable of at least burning the skin of a school suitcase in an instant. She can also use her laser pointer for rapid bursts of fire but at the cost of it breaking the laser pointer. With the military flashlight, she amplifies it to such a degree that she creates a light saber of sorts, which she calls , able to easily pierce through a metal beam. In her battle with Junko, Iruka carries with her several batteries on her person in case their power runs out. For sound waves, Iruka uses a whistle, allowing her to use powerful sounds. Her tools, however, are all vulnerable to water, shorting out or being too wet for use.

However, even without tools such as lasers or flashlights, Iruka can simply use her hand to create powerful flashes of light. Even a single finger from her attack knocked out Shokuhou Misaki. According to Junko,  the flash of light causes an abnormality in the brain's electrical signals. As such an esper who has control over electrical signals, like an esper with Rampage Dress, can endure the attack, though Junko's eyes were still out-of-focus afterward.

Prism eye
Iruka's right eye is a Prism (稜鏡 (プリズム) ), when applied with her powers she can turn the light around her into a laser. Indeed, she later tries overloading it with her powers to create a room of tiny lasers all directed toward Junko. The danger of using this is that it can overheat her prism and her eyesocket.