Armin Arlelt (アルミン・アルレルト Arumin Arureruto?) is a soldier in the Scout Regiment. He is also a childhood friend of Eren Jaeger and Mikasa Ackermann, and is one of the two deuteragonists of the series. Although he appears to be the physically weakest of the 104th Cadet Corps, his high intelligence and strategic genius makes him an invaluable asset, though he does not consider himself to be one and is known to have a low self-esteem.
Armin is rather short for his age, though he has a somewhat muscular build. He has a round feminine face, blond hair that is cut in the style of a bob, large, expressive blue eyes, brown eyebrows, and a slightly upturned nose.
In his childhood, Armin wore a long-sleeved single-buttoned jacket with a collared shirt, long dress-pants and dress shoes. As a member of the 104th Cadet Corps, Armin wears the standard 104th Training Corps uniform with a white button up underneath.
Armin is part of the Scout Regiment and dresses in the standard Survey Corps uniform. Underneath his short brown jacket, he wears a white, collared button-up shirt, similar to the one he wore as an adolescent. Like his fellow comrades, Armin has supplemented his attire with a large green cape when participating in the expeditions outside the Walls. He also has long brown boots that reach up almost to his knees.
Even when he was young, the naturally curious Armin had a deep fascination with the world beyond the Walls. As a child, he found and studied an illegal book about the outside world that was owned by his grandfather. He told Eren Jaeger, his best friend, about the book and the information that was inside it. Armin was branded a heretic by the other children, for his unusual interest in the outside world, and was frequently picked on. Too timid to defend himself, Armin would often need to rely on his friends (Eren and Mikasa) to protect him from local bullies. This, coupled with his frail physique, was a source of much shame for Armin, leading him to have poor self-esteem and believe himself to be a burden upon others. Because of this, Armin has always been very eager to prove his worth. As a child, he hoped that one day he would be able to consider himself a true equal to his friends.
Armin continued to have low self-esteem during his training years and for a short while after graduation. During this time Armin considered himself to be useless and a burden due to his lack of physical strength and physical skill. However, soon after graduation, he came to learn that his mind is an equally valuable asset to the military and that he is not useless or a burden as he can use his brain to help people. Consequently, Armin gradually gains confidence in himself and his abilities. Nonetheless, he can still be hard on himself at times. The fact that he is so willing to sacrifice himself to achieve a goal shows that he still does not value his own life as much as he should.
Armin is exceptionally loyal and selfless. He constantly worries for the safety of his friends. Armin is always prepared to throw himself into dangerous situations to save them, even offering to sacrifice himself for Mikasa. When he, Jean Kirschtein, and Reiner Braun had to decide who would be left behind without a horse, Armin immediately offered himself without hesitation. When Jean was injured in battle, Armin rushed to his aid, placing himself in danger as well. Armin is also very level-headed, keeping Eren and Mikasa under control when their emotions get the better of them. He has talked down a fight Eren started with a soldier and restrained Mikasa from acting rashly during Eren's military trial.
Armin is a very analytical person. He likes to think deeply about situations and solve problems using his mind. These personality traits, in conjunction with his intelligence, good judgment, level-headedness, ability to plan ahead, and ability to come up with creative ideas and think outside the box, make him a great tactician.
Armin has shown great investment in humanity's future and is always striving for and thinking about how he can change things for the betterment of mankind.
Armin's hard and cruel life has caused him to have certain beliefs about how the world works. Armin believes that (in the cruel world in which they live) in order to surpass monsters, accomplish goals or make a difference, you must be willing to sacrifice anything, even your humanity. Armin admires strong leaders such as Erwin Smith, Dhalis Zachary, Ian Dietrich, and Dot Pyxis for their ability to sacrifice themselves and their humanity in order to achieve their goals. He believes that tactical related decisions should be based on logic (what actions will produce the logically best outcome?), rather than emotions.
Before Year 845
Armin and his friend Eren Jaeger were united together as outcasts from the other children in town. One day, Armin discovered a book belonging to his grandfather, describing the outside world. Inspired by what he read, Armin showed the book to Eren. Armin would often spend his time enthusing Eren about the outside world, for which Armin held a passionate curiosity. Reading from his grandfather's book about salty oceans, deserts, and other surreal places, Armin expressed a desire to one day venture out and see these magnificent sights for himself. However, Armin's interest in the outside world was met with frequent harassment by local bullies, who regarded him as a heretic.
In the year 845, Armin would once again find himself cornered by bullies who mock him for his deep curiosity for the outside world. Refusing to fight back, Armin would need to be rescued by the timely appearance of Eren and Mikasa. Later, he and his two friends settle by the riverbank, where Eren broods over his desire to join the Scout Regiment. Just as Armin muses how the Walls can not protect humanity forever, the Colossal Titan appears and subsequently breaches Wall Maria as Armin and the others watch in horror. As Titans flood the Shiganshina District, Eren, and Mikasa head back home to find their doomed mother as Armin tries to stop them, but finds himself petrified by fear. Unbeknownst to Eren and Mikasa, Armin was the one to locate and inform Hannes to save the two as they were going too close towards the Titans' direction.
Armin and his grandfather both managed to board a boat leaving Shiganshina. While sitting with his grandfather, Armin noticed Eren and Mikasa nearby and attempted to go them. He was stopped, however, by his grandfather, who correctly deduced that Eren and Mikasa had just been through a traumatizing ordeal and would not want to talk. Armin was perplexed by this but was soon distracted by the sight of an Armored Titan smashing the inner gate of Wall Maria.
After escaping Shiganshina, Armin's grandfather was drafted to help try to reclaim the lands lost after the fall of Wall Maria. However, he, like most who participated, waw killed during the mission, and Armin was left as an orphan. Despite being told that his parents were participating in a Recovery Operation, Armin knew that his grandfather and the other civilians had been sent on a suicide mission so that there would be fewer mouths for the government to feed. With no family left, Armin moved onto a settlement with Eren until the two of them turned twelve, and were able to join the Military.
No longer content with sitting by in the face of the Titan threat, Armin decides to enlist into military training along with Mikasa and Eren. He was able to pass the basic aptitude test after some effort and tried to help Eren with it when he struggled to stay upright. Although high in intellect, Armin was considered weak in physical strength and graduated below the top ten.
In 847, Armin is formed a team with Jean during an omni-directional mobility gear drill in Trost District. Unlike Jean, he is cautious of overstepping their training territory. Armin tries helping Jean through the day, helping him prepare for a cooking competition.
In 848, Armin is assigned the role of data collector in his group during a wilderness exercise, led by Marco. His group is ambushed and Christa Lenz is captured. His teamwork to rescue her and he gives his findings to Keith Sadies at the end of their excursion.
During the night after their graduation and before the trainees had decided on their chosen section of the military, (Military Police Regiment, Garrison, or Scout Regiment,) Armin sits with Eren and Mikasa to eat, and watches as Eren responds to a taunting Jean, by finally deciding to set the record straight and gives a moving speech to the whole of the 104th Training on how he wants to kill the Titans to gain freedom and pursue his dream to see the outside world beyond the entrapment of the Walls.
After the dinner, Armin finds Eren and Mikasa sitting outside of the building and joins them, saying that the party is over and that they should head back to the dorms. Before they do, Eren asks Armin which section of the military he will be joining. Armin sits down and reveals that he will join the Scout Regiment along with Eren and Mikasa. Eren questions his choice incredulously, knowing of Armin's physical weaknesses. Armin affirms his worries by acknowledging that he is physically weak. Eren responds supportively but advises Armin not to join Eren's own crazy course of action while neglecting his own strong points. Armin responds bitterly determined, saying that he would rather die than become a burden.
Before Eren or Mikasa can answer, they are interrupted by seeing Hannes, who they now salute as the Captain of the Garrison. Hannes points out that its been 5 years since he is seen them. He then mentions that he still has no idea where the missing Dr. Jaeger even is, and that Eren is possibly the only one with memories as to his whereabouts and asks him of he can remember anything. Eren then collapses, worrying Hannes, Armin, and Mikasa who he tells that even though this happens to him, he is still unable to remember.Trost. He trembles in fear, realizing how sorely unprepared they are to respond, but Eren manages to shake him out of it. Later, Armin joins Eren's squad in the middle guard of Trost and exchanges confident words with Eren about killing Titans, and soon after departs with Mina Carolina, Thomas Wagner, Milieus Zeremski, and Nack Tierce to their assigned location. Along the way, Thomas is caught by surprise and eaten by an abnormal Titan. Enraged and vengeful, Eren charges ahead of the others to engage the Titan, and Armin and the others follow suit. However, the group is ambushed and picked apart by the surrounding Titans, leaving only Armin alive and Eren missing his left leg. Shocked and horrified, Armin is left immobile as a nearby Titan plucks him up and attempts to swallow him. Eren, just barely conscious enough to remember how Armin inspired him to see the outside world, leaps to Armin's aid; just barely saving him from being swallowed. Eren hurls Armin out of the Titan's mouth, but is eaten in his place as Armin screams in anguish.
Stuck in a state of shock for some time, Armin is shook out of it by Conny who questions where the rest of his squad is. Armin suffers a mental breakdown, despising himself for his cowardice that resulted in Eren's death. He leaves to inform the rear guard of what happened, along the way lamenting how the world is and always has been hell. On the way, he encounters Hanna trying to resuscitate Franz. Armin beckons Hannah to stop, seeing all too well that Franz is bisected and already dead.
Armin is later confronted by Mikasa above the rooftops with the other stranded trainees. She questions him about Eren's location, but as soon as Armin looks at her with tearful eyes she understands. Armin blurts out the names of all the fallen soldiers in Eren's squad, ending with Eren himself. Despite his clear regret, Mikasa calmly comforts Armin and explains that they must not get emotional at a time like this. Armin follows as Mikasa guides the leaderless trainees to safety, but realizes how she is only masking her distress. When Mikasa carelessly uses up all of her gas, Armin comes to her aid. Soon after, Armin, along with Mikasa and Conny, witness the appearance of the mysterious Titan who only kills other Titans.
With Mikasa's gas is exhausted, Armin provides her with all the remaining fuel and blades he has, seemingly ready to remain behind. Armin requests to keep one blade, implying to commit suicide with it, but Mikasa and Conny refuse to leave him behind. With Trost's military headquarters overrun with Titans, and the soldiers running low on fuel, Armin devises a plan to lure the Rogue Titan towards the HQ to wipe out the surrounding Titans. Once inside the HQ, Armin constructs a plan to eliminate the Titans infesting the supply depot inside. While Armin and several other soldiers act as bait, members of the 104th's top 10 would slay the seven Titans without having access to their omni-directional mobility gear. Armin's strategy works, and the trainees refuel their equipment. Shortly after, Armin witnesses Eren mysteriously emerge from the Rogue Titan's nape, unconscious, but alive.
After being recovered, Eren was detained by a group of soldiers and was going to be executed. Armin and Mikasa defend him, as he wakes up surprised and confused. Eren plans to escape over the Walls unless Armin is able to convince the soldiers of Eren's value to humanity. Eren tells him that his quick thinking has saved him and Mikasa before, as he was the one who went to Hannes when Shiganshina was being attacked. Armin, more confident than ever, walks into the open and tries convincing the soldiers of Eren's strategic and tactical importance in turning the tide of the battle in Trost. As a soldier, he passionately declares to be ready to die for this cause and makes a grand salute. Pixis noticing his determination and passion, prevents their execution.Now with a boost in self-confidence, he tells the senior strategists that Eren could carry the boulder over to the hole while other soldiers could lure the Titans towards the Walls. They proceed with the plan. Later, when Eren loses control of his Titan form and knocks himself out, Armin rushes to Eren and lands on his back. Remembering the spot where Eren had risen earlier, Armin stabs into him a little askew so that it would not be fatal, but would wake him up. He reminds Eren of his personal vendetta against the Titans, but Eren only becomes responsive once he reminds him of the world beyond the Walls and asks him to think of the reason he wanted to go out there to begin with. Eren, successfully motivated by Armin's words, carries the boulder and plugs the breach and all the remainder of the fighting is from then on supported by the newly returned Scout Regiment.
Armin is then present as a witness to the hearing that decides Eren's fate as now being revealed Titan, which ultimately decides for him to be placed in the custody of the Scout Regiment's Captain Levi. He and Mikasa are then separated from Eren until they are able to join the Survey Corps.
Before the trainees are able to decide their chosen military paths, the news spreads that two captured Titans, Sawney and Beane, were slain, and Armin along with other trainees from the 104th Trainee Squad are called in for inspection. Armin, Annie, and Conny discuss which branch of the military they would join. To the surprise of Conny, Armin declares he intends to join the Scout Regiment. Annie compliments Armin on his courage, but states she still wants to join the Military Police Regiment and survive. To Annie's surprise, Armin tells her she is also good person because he can tell she does not want them to join the Scout Regiment either. She disagrees saying that she is not a good person, because she just wants to assure her own survival by joining the Military Police Regiment.
After joining the Scout Regiment with Eren, Mikasa and the rest of the 104th's top 10 (excluding Annie Leonhart), Armin participates in the Scout Regiment's 57th expedition, venturing beyond Wall Rose. Not long into the expedition, Armin's squad encounters the Female Titan, which is seemingly highly intelligent and knowledgeable about the Military formation. The Female Titan kills Armin's entire squad, but spares Armin's life after carefully removing his hood and observing his face. As the Female Titan moves on, Reiner and Jean meet up with Armin and the three pursue the mysterious Titan. Armin suggests the Female Titan, like Eren, is a shifter and is likely hunting for Eren. The three attempt to engage the Female Titan, and are nearly killed, but manage to stall her, though she immediately beelines for Eren's direction after warding Armin's group off.
Though they survived the encounter, Armin, Jean and Reiner are left stranded with only one horse, which is only strong enough to carry two at a time. After being bandaged up by Reiner, Armin offers himself to be left behind, but luckily, Christa quickly arrives with two spare horses in tow.
Reaching the Forest of Giant Trees, Armin and his fellow soldiers perch on its many high branches, distracting Titans while Erwin confronts the Female Titan. While they wait, Armin concludes that Erwin withheld vital information from most of the soldiers out of fear of traitors existing amongst them. Jean criticizes his commander's actions, but Armin defends Erwin, stating that playing it safe will not bring about change. When the expedition ultimately ends in failure, Armin safely returns to Wall Rose with the remainder of the Scout Regiment.
Sometime later, in Stohess District, Armin locates and asks Annie, as a Military Police member, for her help in hiding Eren as they need to flee Wall Sheena to avoid Eren's inevitable execution. Although initially hesitant, Annie accepts, and Armin explains that they must smuggle Eren out of Wall Sina by foot and will take an underground route. As he, Eren and Mikasa enter the underground, Annie refuses to continue on, realizing that Armin has led her into a trap. Armin confronts Annie, questioning why she was in possession of Marco Bodt's omni-directional mobility gear inspection. Annie claims that she simply found it, but admits to having killed the two captured Titans using her own equipment when Armin accuses her of such. Annie questions why Armin did not take action if he was already so suspicious of her, but Armin states he simply could not believe it, and questions why Annie chose to not kill him when she had the chance. Annie is not sure herself but congratulates Armin on managing to corner her, confirming her identity as the Female Titan-shifter.
Armin fires a sound grenade, signaling hidden soldiers to restrain Annie. Despite their efforts, Annie succeeds in injuring herself using a barb hidden in her father's ring, allowing her to transform. Anticipating this, Mikasa grabs both Eren and Armin and takes them further underground as Annie in her Titan form attempts to grasp them. Seeing that his strategy has failed, Armin initiates plan B, trying to encourage Eren to fight Annie. Eren tries repeatedly to assume his Titan form, but cannot due to his reluctance to fight Annie. Having no other option, Armin suggests he and Mikasa distract Annie so that Eren may safely flee. Realizing that if he does not fight, his friends will surely die, Eren finally transforms into a Titan and fights Annie.
After realizing that she is fighting a losing battle with Eren and the Scout Regiment, Annie decides to make her escape by climbing over the Wall. As Mikasa, Hange, and another Scout scramble to catch up to her, Armin realizes that they will not be fast enough and instructs Eren in his Titan form to propel Mikasa up the Wall so that she can gain enough speed to overtake Annie. Mikasa cuts the Female Titan down and Eren pins her to the ground, allowing for the other Scout Regiment members to extract Annie from the nape of the neck. When Eren awakens from his Titan form, wondering Annie's fate. Armin informs him that no one knows, as Annie encased herself in rock hard crystal.
As Eren rehabilitates from his ordeal, Armin takes a moment to rest with the others. Armin informs Jean that Eren's summons to the King was canceled and that Annie is indeed the Female Titan. She is been detained underground after encasing herself in a crystal to avoid interrogation. Reflecting on the mysterious Titans found in the Walls, Armin observes that for all these years they were being protected from the Titans by Titans. Armin cannot fathom how the Walls were built in the first place but hypothesizes that abilities like Annie's hardening power were somehow employed to construct the Walls.
After Wall Rose is declared to have been breached, Armin, Mikasa, Hange, Eren and Levi ride in a carriage out Ehrmich District. On the way Armin thinks that if they can use Eren's hardening in his Titan form, then they could seal up Wall Rose, and quite possibly Wall Maria as well. Hange likes this plan, and while Eren tries to protest, Levi stops him, saying that he has no choice but to do it.
After rescuing Reiner, Bertholdt, Krista, and a mortally wounded Ymir from Utgard Castle, Armin and the rest of the Scout Regiment regroup on top of Wall. However, Armin and the remaining Scout learn about Reiner and Bertholdt's secret identities, the Armored and Colossal Titan respectively. Mikasa tries to kill the two, but fails, and they both transform above Wall Rose, taking Eren, but not before he can transform and engage Reiner in battle.
As Bertholdt emits steam from his body, Hange suggests that he might be trying to disappear again, but Armin suspects otherwise. He says that while last time the Colossal Titan vanished instantly, this time he is protecting himself with steam, and if this keeps up, they will not be able to attack him. Armin shoots a cable at Bertholdt's arm, but it goes off-course, and Armin panics, asking what are they meant to do now, to which Hange replies, they wait. As Eren battles Reiner, Armin suggests that Eren move back towards the Wall, as their goal is to kidnap him and take him away. Eren begins to turn the tables on Reiner, but just then Reiner roars, signalling Bertholdt, who falls on top of them from the Wall.
Once Eren is kidnapped, Mikasa and Armin sit atop the Wall, injured. As Mikasa expresses regret for not being able to save him, the two reminisce about the childhood they had before Wall Maria was destroyed. Hannes joins them, and gives them both their cracker rations, which they eat quickly. Along with some Scout Regiment reinforcements, the Garrison and Military Police soldiers, they go to retrieve Eren and Ymir from Reiner and Bertholdt's hands.
As Armin and the rest of the group near the forest of giant trees where Bertholdt and Reiner are resting, they are overcome with Titans. Once they encounter Ymir's titan form, Armin notices that Ymir is suspiciously watching everybody and neglecting to attack them. Krista appears and Ymir catches her, escaping, and Armin realizes that she must have sided with the traitors.
Reiner transforms into the Armored Titan and escapes with Bertholdt, a restrained Eren, and Ymir in tow. Following on horseback, Armin states that while Reiner is slow, it will be hard to defeat him as he has not shed any armor. Eventually, Armin succeeds in latching onto the Armored Titan. He and the other members of the 104th futilely try to persuade Bertholdt into handing over Eren, but they are forced to get off of the Armored Titan as Erwin charges towards them, leading a horde of Titans.
The giant mass of Titans approaches Reiner and Bertholdt, along with Ymir, and slow him down to a crawl, with Erwin using this opportunity to order the soldiers to retrieve Eren. In the confusion, Armin latches onto the Armored Titan's head and confronts Bertholdt. Remembering what he said before, that somebody who cannot abandon something, cannot change anything, Armin decides that he must throw away his integrity. He taunts Bertholdt, telling him that they are torturing Annie as they speak, in every way possible, and that her "screams" taught them something, that even with her body's healing she can never get rid of the pain. Bertholdt becomes enraged, stating that he will kill them, and Erwin uses this opportunity to free Eren from Bertholdt, severing one of his maneuvering cables in the process.
Reiner throws Titans at the fleeing soldiers, knocking Jean unconscious and throwing him off his horse. Armin defends him from Titans, and is saved after Eren activates the Coordinate and causes all the Titans to attack the Smiling Titan and the Armored Titan. Erwin uses this opportunity to retreat, and they make a full retreat. Once they return, Armin and Jean theorize that it was Eren who caused all those Titans to attack.
Being physically weak, Armin is rarely assigned to the front lines and rarely uses his omni-directional mobility gear for direct combat. Instead, his greatest strength lies in his intelligence - innate abilities of deduction and strategy formulation, be it in a war room or on the fly. But Armin has a keen eye for detail, making him a remarkable field tactician, a trait that distinguishes him among his fellow trainees. His strategies help save his fellow soldiers numerous times.
- Eren Jaeger - Eren is Armin's best friend from childhood. As children, Armin looked up to Eren, as he was always there to protect Armin from bullies regardless of the odds. It was Armin who enthused Eren about the outside world, and together the two would dream of venturing beyond the Walls. Initially, Armin felt inferior to Eren, ashamed of being in need of his protection, and lacking the courage his friend boasted. Despite this, it was Eren who gave Armin the confidence to begin using his strategic mind to its full potential, reminding him of the many times his reasoning and quick thinking have saved them. As soldiers, the two share the most powerful bond and, using their own unique abilities, had saved each other numerous times.
- Mikasa Ackermann - Mikasa is a close friend of Armin's. Whenever Armin got into trouble with local bullies, Mikasa would come and save him. Armin looked up to Mikasa's strength and courage and felt inferior to her. Mikasa, however, believes in Armin's abilities to reason out the best solution in a dire situation and trusted him deeply. She was responsible for boosting Armin's confidence and shaping his character.
- Jean Kirschtein - While Armin was initially not that close to Jean due to the latter's rivalry with Eren, their relationship has changed considerably since joining the Scout Regiment. Armin's growth as a strategist has aligned with Jean's growth as a leader, and the two often share insights or opinions with one another.
- Annie Leonhart - The two share a mutual respect for each other, expressing admiration for each others' hidden qualities. This causes her to hesitate when attacking in her Titan form, a mistake which allowed Armin to discover her true identity. He then uses emotional blackmail in order to lure her into a trap and facilitated her eventual capture.
- Reiner Braun - Reiner is shown to have been protective of Armin, helping him during physical training exercises and carrying him to safety during dangerous operations.
- Marco Bodt - Armin noted that they were friends, and did maintenance of their equipment together. This later allowed him to recognize Marco's stolen equipment when it was presented by Annie as her own.
- Erwin Smith - Armin holds the Commander of the Scout Regiment in high esteem. Although he cannot always guess his superior's inner thoughts, Armin regards him as a highly smart person and a very capable commander who is not afraid of making sacrifices to reach his goals.
- The voice of Armin and the narrator of the anime are shared by the same voice actors in Japanese and English, Marina Inoue (in Japanese), Josh Grelle (in English).
- In the side art for Volume 11, Armin, along with a few other characters, were depicted transforming into a Titan. His form had a large head that was almost the same size as his small body. This was also included in the second OVA.