On their journeys, Rin and Jaken often rest on his back to fly over great distances. When Sesshōmaru leaves Rin in a safe place, A-Un stays with her as her protector.
A-Un wonders what was the light comes from, and later follows Sesshōmaru. After the defeat of Sō'unga possessed Inuyasha by Kagome Higurashi, A-Un lay down next to Mō-Mō as Rin thanks to Kagome saving her and Jaken's lives and gave her the Beads of Subjugation. At the phantom castle, A-Un defeats many of Takemaru of Setsuna's zombie warriors. After Takemaru defeated, A-Un escape the castle as Sō'unga is opening the path to Underworld, and under the protection of Saya's barrier. After the final defeat of Sō'unga by Inuyasha's Bakuryūha and Sesshōmaru's Sōryūha, it has been sealed to sealed to the netherworld and seen the spirit of their father Tōga and A-Un continues to follow Sesshōmaru.
Hanyō no Yashahime
After Kirinmaru's older sister Zero put the Silver Scale Curse on Rin's neck, Sesshōmaru and Jaken rode on A-Un as they took her to the Sacred Tree of Ages. Four years later after Homura set the forest on fire under Zero's order in an attempt to kill Towa and Setsuna, A-Un was instructed to take Setsuna to the Hanyō Hidden Village.
A-Un is quite a benevolent and laid-back creature, subservient to Sesshōmaru and even to Kohaku, Rin (although this could be due to the kindness Rin has shown the creature) while only occasionally obeying Jaken, who sometimes has trouble motivating the demon to move; A-Un was implied to actually have little to no respect for Jaken in the 3rd movie when Jaken encouraged Sesshōmaru not to team up with Inuyasha, prompting everyone (A-Un apparently included) to rearrange his face to change his mind, showing A-Un is much more intelligent than he looks and that he could understand the situation at hand. This also showed when he merited the two dog brothers' teamwork. A-Un's benevolent nature may be due to the fact that he is one of the only two yōkai in the series who is explicitly stated to be an herbivore. A-Un is intelligent and is a sentient being; he also seems to have a sense of humor. The closest counterpart to A-Un in the series in terms of personality would be Kirara, a demon who also cannot speak but does possess a great deal of intelligence and loyalty.
A-Un is a brown dragon yōkai that looks like a horse and had two heads, plus they wears a black mask while the rider holds the leash. As for humans like Rin, he has a saddle that can carry her, even others like Miroku, and Kohaku.
Powers & Abilities
- Flight: A-Un possesses the ability of flight in a manner similar to Tōtōsai's three-eyed ox yōkai Mō-Mō - an ability which is used to the advantage of Sesshōmaru when it comes to traversing great distances. A-Un typically carries Rin around on its back as she is not fast enough and does not possess the stamina to keep up with Sesshōmaru when they travel.
- Lighting Blasts: A-Un can shoot bursts of energy similar to lightning bolts out of its mouths. From the right head, "A", it fires beams of blue lightning to attack its enemies when it is roused into battle. The left head, "Un", fires green lightning which allows him to control clouds and possibly the weather. However, this ability has never been used to directly attack anything and it’s possible that it isn’t harmful.
The Dog Demon Lord in control of A-Un. A-Un has been traveling with Sesshōmaru as a servant for a long time, longer than his vassal Jaken and especially longer than his most recent traveling companion, Rin.
The young human girl traveling with Sesshōmaru has a special relationship with A-Un. Rin named the demon and cares for him, as such A-Un looks after Rin in turn, protecting her and allowing her to ride on his back. A-Un has saved Rin on multiple occasions. The two most memorable examples are when he saved her from some lesser yōkai while she is collecting herbs to save Jaken when he is poisoned by Naraku's miasma, and when he protected her from the zombie warriors in Swords of an Honorable Ruler. If Rin is in danger in his presence, he will do everything he can possibly do in order to protect her.
The demon vassal of Sesshōmaru had a somewhat strained relationship with A-Un, apparently struggling to control the demon, unlike Sesshōmaru, Rin and Kohaku who A-Un willingly obeyed without question.
It seemed that A-Un had no trouble being led by Kohaku when he joined the group and let him ride on his back all the time.
- It is undecided whether A-Un's name can be translated into anything applicable to their character, but the pronunciation a-un is used to describe a sound influential in many Indian religions "indicating an inherently harmonious relationship or non-verbal communication" (A-un). Also, a-un is a term typically used to identify the 'one open mouth and one closed mouth' komainu statue sets normally seen near or in shrines.
- A-Un is one of the only two yōkai in the series who is explicitly stated to be an herbivore (the other being Mō-Mō).
- "A-Un" may be in reference to a pair of stone gargoyles (or Koma-inu, Nio Protectors of Japan): Agyo and Ungyo. They're usually represented with one having the mouth open and the other having its mouth closed. They're protectors against holy spirits, which could explain A-Un's benevolent nature. Koma-inu craftsman in Japan refer to Agyo and Ungyo as "A-Un" for short.
- Episode 20 (Appears in a flashback)
- Episode 27 (Appears in a flashback)
- Episode 31 (Appears in a flashback)
- Episode 37 (Appears in a flashback)
- Episode 47
- InuYasha anime; Episode 96
|Incarnations||Kanna • Kagura • Goshinki • Jūrōmaru • Kagerōmaru • Musō • Infant • Hakudōshi • Byakuya • Akagane|
|Rejected parts||Unnamed incarnation • Hair monster • Eye monster • Onigumo (reabsorbed) • Kugutsu|
|Allies||Saimyōshō • Sesshōmaru (formerly) • Tsubaki • Hakushin • Shichinintai • Abi • Tekkei • Mōryōmaru • Mirror demon • Magatsuhi|
|Enemies||Kikyō • Inuyasha • Kagome Higurashi • Miyatsu • Miroku's father • Miroku • Sango • Kirara • Kohaku • Kōga • Sesshōmaru (currently) • Kaguya • Mōryōmaru • Hitomiko • Kansuke • Kaede • Midoriko • Rin • Jaken • A-Un|
|Miscellaneous||Shikon no Tama • Kazaana • Onigumo's cave • Naraku's castle • Mount Hakurei|