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Summary:

“I’m no expert on the matter,” Mustang begins, “but from what the Elrics have explained to me, there are differences between this universe and every other. Those differences inform the transmutation circle that is drawn, so that the process of returning you is less likely to result in a rebound.
“Unfortunately,” he emphasizes, before Shouta can ask what half of those words mean, “one of the key differences between this universe and all the others we’ve encountered so far is that we have functional alchemy. I’m assuming you’re entirely unfamiliar with the concept?”
Shouta resists the urge to bristle at his slightly exasperated tone and simply hums in agreement.

Notes:

(See the end of the work for notes.)

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“Colonel Mustang,” the man introduces himself, offering a wary handshake. 

Shouta takes it, suspiciously eyeing the militaristic uniform and weapon holstered at the man’s side. Colonel seems very likely. He doesn’t offer his own name in return, just to be safe. 

“We have some alchemists working on a transmutation to return you and the other… visitors to your original…” The colonel seems to flounder for an appropriate word.

“Universes?” Shouta offers tiredly. He’s already accepted that this situation is impossible and horrifically beyond his understanding. Alchemists. Transmutation. This is certainly not the Earth that Shouta is familiar with. 

The colonel, on the other hand, seems to still be wrestling with this reality. “Universes,” he admits with a stiff nod, eyes narrowing like he can’t quite believe what he’s saying. 

“It’s easier for them to figure out if they have more information about where you came from,” Colonel Mustang continues, face smoothing into a polite mask. “Many of the other visitors we’ve had were too… combative to make conversation. Mind you, the Elrics managed to get them back all the same, but it’s much easier for everyone involved if you cooperate and assist them in locating the correct universe to send you back to. 

“So. Would you be willing to come with me and speak to them, or are you going to go crazy and try to overthrow our government?” 

Shouta blinks. It seems a stupid question, what with how he’s outnumbered by an entire universe to one, and a universe with operations Shouta doesn’t even know the shape of, if they’ve been getting many people transported here from other worlds against their will. But there’s a certain weariness with which Mustang speaks that makes Shouta think that it’s not only happened before, it’s happened frequently. Idiots. 

“If your only intention is to get me back home, unharmed, then I have no reason to fight you about it,” he replies carefully. 

The colonel’s tight shoulders relax almost imperceptibly. “I’ll take it. Let’s get going.” 

 

The walk down the hallway away from the holding cell to wherever they’re going is tense and dark. Shouta is fairly certain they’re somewhere underground, and the dim lights shoved up in the corners of the low tunnel don’t do much against the feeling of being buried. The colonel’s heels click sharply on the stone floor, and Shouta does his best to allow his own boots to land with weight. He suspects that his usual tactic of moving in silence would not be well received in this situation. 

“So,” Shouta tries to break the silence. “Who are these alchemists’ I’m going to talk to, and how will that get me home?”

The Colonel looks like he’s trying not to sigh heavily. Shouta empathizes. 

“I’m no expert on the matter,” he begins, “but from what the Elrics have explained to me—” (There’s that name again, the Elrics. Shouta commits it to memory.) “—there are differences between this universe and every other. Those differences inform the transmutation circle that is drawn, so that the process of returning you is less likely to result in a rebound.

Unfortunately,” he emphasizes, before Shouta can ask what half of those words mean, “one of the key differences between this universe and all the others we’ve encountered so far is that we have functional alchemy. I’m assuming you’re entirely unfamiliar with the concept?” 

Shouta resists the urge to bristle at his slightly exasperated tone and simply hums in agreement. 

“Alchemy, at its simplest, is the ability to break down atoms and transmute them into different arrangements. The process is guided by drawn circles, which assist in channeling energy and directing the movement of particles. However, once you move beyond the basic chemistry aspect—” (Shouta’s always been bad at chemistry, dammit.) “—it becomes exponentially more difficult to explain or to perform. It is a science, which takes significant intellect and many years of education to master. Some of our prior visitors have found it either incredibly off-putting or have been enraptured by it.” 

“Any sufficiently advanced technology is indistinguishable from magic,” Shouta offers, unsure if this is a scientifically accurate assessment of what’s being described, but it makes him feel better about not knowing what the hell is going on. 

“Essentially, yes.” The colonel gives him another appraising look, and Shouta thinks he’s making out slightly better in Mustang’s perception. “The two alchemists you’re about to meet are prodigies. They’ve been able to push the bounds of alchemy, combining it with other practices and formulating techniques that are incomprehensible even to other accomplished alchemists. They are the only people in the world who actually understand how to send you back. Understood?” 

Shouta meets the colonel’s eyes. “I understand,” he replies, attempting to convey that he gets the unspoken message. These two people are going to help him, they are the only ones that can, so Shouta needs to stay in their good graces. Whether or not that’s actually true is besides the point, so long as Shouta can get back home. 

“Good.” 



“You’ve mentioned the Elrics several times now. Are they the two alchemists we’re going to see?” 

Colonel Mustang hums in assent. “Edward and Alphonse Elric. You may also hear some refer to them by their State Alchemist titles, Fullmetal and Goldheart.” 

“State Alchemist?” Shouta inquires. 

“Yes. I told you before that alchemy is challenging to master. Those that excel are employed by the state for their services, and assigned titles in recognition of their excellence, in whatever area that may be.” 

“And your title?” Shouta asks. 

“Pardon?” Mustang stops walking, and Shouta stops with him. He prays quickly that he’s not sentencing himself to death somehow. 

“When I arrived, someone called to get an alchemist. You showed up. Your gloves have what I assume to be the transmutation circles you described earlier. And you’ve admitted yourself that you’re a colonel, so you are obviously affiliated with one state or another. I don’t believe it’s too far of a leap in logic to assume that if you’re already serving in the military, you would also be a State Alchemist.” 

Colonel Mustang gives Shouta a long, silent look. It’s carefully blank, but obviously considering. His dark eyes reveal nothing; they are simply cold. Luckily, Shouta has a lot of practice not letting his nerves show. 

“Flame.” The Colonel finally says, flourishing one hand strangely to display that bright red embroidered design. “I’m the Flame Alchemist. I’m just now realizing that I haven’t caught your name.” 

Shouta’s willing to bet money that this man didn’t just realize it.

“Aizawa Shouta.” 

He’s just decided that Shouta’s worth putting a name to. And Shouta’s not sure he should be flattered. 

“You’re mostly correct, Aizawa Shouta,” Mustang says with an air of faux casualty. “Although, you’ve gotten one thing a bit backwards. State Alchemists are automatically assigned the rank of Major upon passing their exams. I’m just one of the few who has been promoted beyond that.” 

Translation: he’s not a State Alchemist because he’s a colonel. He’s a colonel because of his ability or performance as a State Alchemist. 

Shouta may have barely scraped past chemistry, but he remembers his lessons in civics and history well. Nuclear bombs came before their power plant counterparts. The entire point of the development of the Hero Commission, initially, was to avoid the predatory practice of military recruiting individuals with destructive quirks and creating armies of weapons of mass destruction. The UN went ahead and formalized the transfer from militaries to the Global Hero Commission to prevent pure genocide, but it took years of lobbying and billions in funding. Humans in power have never been reluctant to use the most powerful means at their disposal for political gain, casualties be damned. 

With a title like Flame Alchemist, Shouta can guess what this man has done to rise in military ranks. But then, he’s done things he’s not proud of as a hero, as well. Even All Might has killed, when there was no other option. It’s not an immediate condemnation, but it’s enough for Shouta to know that this man is not to be taken lightly. 

From the look in Mustang’s eyes, he knows what’s going through Shouta’s head, and he’s waiting to see if Shouta will either balk at the implications or turn hostile. He’s holding one hand perched almost casually by his chest, but his fingers are pressed together tightly. Shouta’s willing to bet it has something to do with those gloves, the circles on them, and being ready to defend himself. It’s not something he wants to test.

“So the Elrics, are they also beyond the rank of Major?” Shouta offers a natural change in the conversation’s direction. No need to press further into a dangerous topic this soon. 

The Flame Alchemist smiles, and they resume walking. “You’d think that, wouldn’t you? They’re certainly capable enough. But no. They have turned down every offered promotion, quite vehemently, in fact.

“There are many factors that often lead people to underestimate the Elric brothers, chief among them is their position as the youngest State Alchemists in this nation’s history. Can I trust you to not make the same mistake, Aizawa Shouta?” 

“How young?” Shouta asks instead of answering, his mind briefly running away from the situation at hand. Because if all State Alchemists are military, then being the youngest implies not only a precocious intelligence, as Mustang had all but stated, but also a life as a child soldier. Hypocritically, Aizawa is suddenly feeling very protective of these brothers he hasn’t yet met. 

He knows that heroics replaced the military in his universe. For all that they are supposed to be apolitical and ultimately moral, the issue of violent quirk-enhanced combat was never actually solved. And his own homeroom class has more than proved that in his own world, his own country, his own children are fighting in wars that should be left to the adults. 

Mustang’s eyes are cold again as he answers. “Old enough to handle themselves, and certainly old enough to demand your respect.” 

Before Shouta can protest (their age is not a factor in his respect) or clarify (he meant when they joined, when they were first exposed to violence and combat), Mustang halts at a door that looks much the same as all the others they passed. 

The colonel opens the door to reveal two people in that same blue uniform, presumably Edward and Alphonse Elric, crouched on the floor, books lying open around the edges of the room, the majority filled with a large chalk circle, the center maybe half-filled with complex designs similar to the geometry on Mustang’s gloves. A transmutation circle. 

“Fullmetal, Goldheart.” 

One figure immediately snaps his head up and offers what Shouta is fairly sure is a messy approximation of a salute. His complexion is darker than Mustang’s, and he has short, dark blond hair and sharp-looking golden eyes. 

“Colonel!” The way he chirps the word is more like greeting a friend than reporting to a commanding officer, although there’s a significant amount of respect, as well. Perhaps closer to the way that Shouta’s students call him “Sensei.” 

His companion (brother?) with a long golden braid, who has his back to the door, only holds up a single middle finger and mutters something that sounds a lot like “bastard.” Shouta finds one of his eyebrows raising against his will. Interesting. 

Colonel Mustang seems to completely ignore the less than friendly response and speaks to the alchemist with the sloppy salute. “Alphonse, this is Aizawa Shouta. He seems competent and cooperative enough to assist with your efforts to return him home. You know the drill.” 

And with that glowing review, the colonel steps out and closes the door behind him, leaving Shouta with the two alchemists who are supposed to somehow transmute him home. 

“Hello!” The shorter haired one, Alphonse, turns a beaming smile to Shouta. Compared to Mustang’s iciness, his cheer is practically blinding. “It’s nice to meet you! I’m Alphonse Elric, and that grump over there is my older brother Edward Elric. You’re welcome to call us Al and Ed; just about everyone does. What do you prefer we call you?” 

“…Aizawa.” Shouta answers at length. He’s a bit busy trying to figure out how old Al is. Young, as Mustang warned him, but not so young as to be truly horrifying. Perhaps as old as his third year students? The uniform fits him well, and it might be making him seem older. 

“Aizawa,” Al repeats, “that’s a cool name! Did Mustang brief you about the basics of what we’re trying to do?” 

“Mostly,” Shouta answers, peering over the back of the aforementioned Ed at the partial transmutation circle. “I’ll admit, coming from a world without alchemy makes it a bit difficult to understand, but I’ve never been dragged into a portal to another dimension before. I’m willing to assume you have the expertise required.” 

For some reason, that makes Al laugh. Shouta’s willing to bet that this brother is Goldheart, based solely on personality. 

“Expertise is a bit of a stretch,” the one who must be Ed pipes up, much gruffer than his brother. “This only started happening a few months ago, and Al n’ I only figured out how to reverse it weeks ago. Not like this shit is easy for us.” 

“…It seems very complicated,” Shouta offers. “The colonel mentioned that you were the only ones capable of reversing it, though. I’d imagine that still makes you the resident experts.” 

Ed sighs from the floor, and finally looks up at Shouta. His eyes are equally as gold and bright as his brothers’, although his face is a bit more angular, twisted into what could be a permanent scowl. They are obviously related, and equally as clearly, very different from one another. 

“Well, in order for it to work, we need to narrow down the range of worlds you could have come from so we can finish the circle.” 

“And since Ed is such a fantastic conversationalist,” Al cuts in, “people usually find it easier to talk to me.” 

Shouta looks between them. One beaming, one glowering, both apparently prodigies capable of holding their own in military roles, so presumably skilled in combat. The beginnings of a comparison start to build in the back of Shouta’s mind. He imagines that the matching headache will follow soon enough. 

But these aren’t his students. He’s a stranger to them, and he knows his own first impressions are often pretty abysmal. 

“I don’t mind,” he tells them both instead, glancing specifically down at Ed. How much of that attitude is his natural personality, how much is defense mechanism, how much was born after atrocities seen in war? “Tell me what you need to know, and I’ll tell you if I can. I only want to get home.” 

 “Great!” Al chimes, and his grin looks just a touch more genuine, now. “Well, you already said that you don’t have alchemy where you’re from, so that helps. Is there any specific trait or technology that you’ve noticed so far that our world is missing compared to yours? Like, we’ve had people come from places where everyone has wings, or auras, or something like that.” 

“…I’m not certain, given that I believe our worlds are at two different points in time,” Shouta hedges, “but I’m assuming that you don’t have quirks here.” 

“Quirks?” Al asks, adopting a more serious expression, confirming what Shouta had suspected since his arrival. 

“Wait, no, what year is it in your world?” Ed cuts in, grabbing for a book in the stack next to him. “We can do the other thing later, but the timing goes in the outer ring, that’s easier to do first.” 

Shouta tells him, and the older brother immediately begins rifling through the pages. The contents appear hand-written, more like a journal than a textbook. He supposed there probably aren’t textbooks relating to portaling people back to their original dimensions. 

“Back to quirks?” Al asks almost immediately. 

Shouta sighs. “Powers, I guess you could call them. People only started developing them several generations ago, very recently in terms of global history. A genetic mutation that has gradually spread to almost the entire population. They vary across individuals, and some are genetically inherited or combined, while others seem to be spontaneously occurring.” 

“Examples?” Ed asks, at the same time his brother says, “What’s yours?” 

“Mine is called Erasure, and demonstrating it is going to be profoundly disappointing here, because it temporarily cancels out the quirks of others. Some are mutation quirks, like having wings and talons, but emitter quirks like mine are more common. I have students with quirks that generate electricity, cancel gravity, and talk to animals.” 

Ed gets up and begins collecting books from the edges of the room. Shouta notices that he doesn’t seem to need to look at his feet to know where the chalk lines are to avoid them. Possibly he and his brother have been using this circle a great deal. 

“Students? Are you a teacher?” Al asks, drawing his attention back. 

“Mm. I teach at a high school for heroes, which, before you ask, is a profession that developed following the appearance of quirks. State militaries were abolished by the United Nations, fearing the implications of political warfare aided by superpowers, so heroes were tasked with combat roles in their stead.” 

“Like a military academy, kind of.” Al guesses, and Shouta nods. Gods, he hates to admit it, but he really is just training soldiers at this point, isn’t he? He might need to change careers after this. “This doesn’t really matter for the array, but… did it work? Did your world just… move on from war?” 

He sounds so fucking hopeful that Shouta wants to beat his own head against a wall. There is a tense minute of silence while he tries to figure out how to explain the convoluted situation that is his entire world

“Yeah, that’s a no,” Ed eventually breaks the silence for him. “You can try all you want, but as long as you have people, there are going to be vendettas and grabs for power and all that shit. The fact that you need heroes—” he spits the word like a curse, and Shouta wonders if he truly knows how right he is in doing so “—to do combat at all means that you still have all of that. No world’s a utopia.” 

“Essentially,” Shouta admits. “Heroes globally are governed by a Commission, with branches in every region, but there are certainly those who are only in it for power and fame. The Commission itself is inherently political, even if they can’t command the actions of individual heroes. More recently, violent factions which are explicitly—” the word villain probably sounds childish to these people “—anti-hero have gained significant traction. We are currently in the midst of the first true war following the appearance of quirks.” 

The Elric brothers meet Shouta’s gaze with twin expressions of solemnity and gravity. These are not children who are shocked with the horrors of war and its makers. These, Shouta remembers, are soldiers, who may or may not have seen war and battle first-hand. The sympathetic shadows in their golden eyes makes Shouta believe it’s the former. 

“I’m sorry to hear that,” Al eventually offers, but Shouta waves the platitude away. 

“At war or not, it’s my world, and I’d like to get back to it.” 

“Working on it,” Ed snaps back, but there’s no real heat behind it. Now the scowl has faded into something just a tad less angry, a bit more focused. Determination.

“That’s actually a fair amount of information to help us narrow down the range. The actual process will involve sending you through a similar portal that you came here through, and if we can get you close enough to the right world, yours will naturally call you back. We’ve found it also helps if we have some sort of symbol that represents the region you want to be transported back to, like a national flag. Incorporating it into the array will help you end up in the right part of the right world.” Al explains. 

“Japan,” Shouta answers, and then nearly smacks himself when he’s still met with two expectant stares. This is a different universe, they probably don’t have Japan. “A white rectangular flag with a solid red circle in the center.” 

Ed huffs a small laugh from where he’s standing, collected books towering in his arms. Shouta sends him a look that usually prompts his students to explain themselves. 

“Sounds like a symbol used in alchemy sometimes,” the blond explains, not looking nearly as intimidated by the look as Shouta’s students are. “More often in alkahestry, actually, which is kind of like the medical version of alchemy from the East. The translation is kind of lame, the scorched blot or something, but it’s often used to target specific wounds or areas. It’s a focus. A good anchor for a portal array.” 

Shouta tries not to think too hard about the implication that his country is a bleeding wound. Maybe if he’s not too late, it can still be healed. He’s not really one for metaphors, and really, it’s just a red dot. Open to interpretation. 

“It’s supposed to be the rising sun,” he says instead, because he’s an idiot who can only remember his history and civics. 

Ed’s brow furrows at him. “Well, then why didn’t they make it look more like a sun, then? Or add a horizon? Even when it’s rising, the sun’s not red.” 

Ed,” his brother admonishes, rolling his eyes. 

“I didn’t design the flag,” Shouta points out, feeling that headache he’d predicted start to take root in between his eyes. 

“Ed’s just being argumentative for the sake of arguing,” Al explains, as if Shouta, a man who teaches high schoolers, hadn’t figured that one out. Although, he wonders how many times Ed has gotten himself in trouble for doing just that. The colonel had said that these two were the youngest State Alchemists in history, and in Shouta’s recollection, militaries were not particularly forgiving to insubordination, even if it came from a teen testing boundaries. Maybe especially not then. He wonders briefly about the Colonel, and how he’d opted to ignore Ed’s middle finger and insult, and unconsciously thinks of a different blond teen who speaks with more curses than not, who refers to him as Hobo-sensei directly to his face, but still gets exemplary grades. The headache grows a touch worse just at the consideration. 

“No offense taken,” Shouta says instead, turning his focus again to the books Ed is restacking next to himself by the largest blank section of the transmutation circle. They’re more journals and notebooks, and if Shouta looks closely enough, he can just make out some of the symbols scrawled within as Ed pages through. 

The page he lands on includes the image of something swirling in an asymmetrical loop around a blank space, and then several options for the symbol which could be placed within the loop. Ed pulls a piece of chalk seemingly from nowhere, and then copies the swirling loop into one corner of the blank space, selecting a very pointy symbol to put in the middle. Shouta can’t help but notice the care with which the alchemist determines which points intersect which lines of the loop. 

“This is probably going to take a while,” Al offers apologetically. Shouta turns to see him crouched by a smaller blank area, deftly chalking triangles and arcs around the pre-existing designs. “Unfortunately, we do need to keep an eye on you, just because of the way that some of the previous visitors have been, but we could call somebody else to take you somewhere a bit more comfortable, if you want.” 

“The Colonel who brought me here mentioned something about the previous visitors,” Shouta says. “Something about trying to overthrow the government?” 

The brothers exchange an exasperated expression that Shouta doesn’t think is aimed at him.

“Fucking morons,” Ed says with a shake of his head, and then goes back to his notebooks. 

“The very first person who came through… well, we think she kind of broke the walls around our world,” Al begins to explain. “She was actually trying to get through to somewhere else, although on her side alchemy was more like magic. Her goal, apparently, was to bring an army through the Gate to conquer other worlds. It didn’t work out well for her. Even worse for the army she tried to drag along with her.” 

Ed cuts in, his expression so severe that Shouta forgets, for a moment, that this boy isn’t a retired pro trying to impart life-saving wisdom on kids who don’t listen. “You can’t force your way through the Gate. The Gate is its own living being, and it will try to consume and digest anything foreign that doesn’t defend itself. Metal armor doesn’t defend shit against something that molds itself between universes.” 

“And the Gate is part of alchemy?” Shouta confirms. 

Al sighs heavily from across the room. “The Gate is more or less the source of alchemy, or at least where we get it from. Before all of this started, Ed was researching how it connects to alchemists in particular, how each individual ability to channel alchemy manifests as a smaller, personal Gate, and how those Gates might be theoretically closed or opened. But the singular Gate, that’s a collection of energy so large that no human can direct it. That first woman, she essentially tore a hole in its side, because in her world, no one had a personal Gate.” 

“Then she went in, unprepared, like a fucking idiot, and the Gate chewed her up and spit her out here, where the connection between the world and alchemical energy was a bit thinner. She came out crazy and violent and missing pieces, although who knows how much of that was her original personality,” Ed finishes. 

Shouta sits with that information for a moment. “And you’re sure that I’m not going to be… chewed up and spit out?” he eventually asks. 

“Yes,” both alchemists answer in unison, and it does make Shouta feel a bit better. 

“We know better than to fuck with the natural order,” Ed says, a bitterness seeping through that Shouta can’t help but interpret as the unsaid word: now. We know better now. 

Perhaps some of his curiosity slips into his expression, because once Ed looks up from his most recent addition to the circle, his face does a quick pass by several emotions before he simply reaches his right arm over to his left leg. Wordlessly, the boy knocks his gloved knuckles twice against his shin, and Shouta hears the clank of metal, dulled by layers of cloth, but obviously not flesh. 

“Hm.” He can’t help the considering hum, even with both of the young soldiers eyeing him carefully for his reaction. (He can see Ed’s predator-locked-on expression, and feel Al’s eyes burning a hole in his back.) Amputations aren’t unheard of, especially for heroes, and below-the-knee is one of the most common, but… that sounded like metal-on-metal. Hand prosthetics, Shouta has heard, are incredibly convoluted and often amputees choose to go without, rather than risk biological rejection and all the other associated complications. He supposes that if you’re a soldier, you’re expected to have both hands. How much was Ed’s choice to have his hand restored, and how much was pressure from others? Does this world do prosthetics differently? 

Shouta doesn’t decide to voice any of that. “So there is some way to return me to my world without going against the natural order, then?” 

“We go with the Gate, instead of against it,” Al answers, and when Shouta turns to face him, he can still feel Ed’s heavy gaze. “It’s like a tide, or a river, sweeping you along. And just like with water, you don’t drown if you have a ship and a map. That’s what the transmutation is, essentially. It steers you to the right tributaries and into the best currents, letting the natural flow of the Gate do the hard work. Of course, it also acts as a shield so that your body isn’t degraded by the energy.” 

So more like a river of acid, Shouta thinks to himself. 

“In this metaphor,” Ed adds, “the transmutation is also doing the work of a dock both here and at your destination. We don’t need to rip a hole in the Gate on this end, because we already have alchemists who can access it through our own personal Gates. Once it gets you close enough to your original world, though, that’s where my research comes in. I can’t construct a personal Gate in someone else, not enough to allow them to perform alchemy or anything. But I can create an opening in the singular Gate that is analogous to a personal Gate, only connected to a world at large instead of an individual. That allows your universe to pull you back to where you belong without completely pulverizing your body or your brain. The transmutation also closes that Gate and permanently locks it behind you, so don’t go getting any stupid ideas.” 

“I just want to get back home,” Shouta says with a sigh. He truly has no desire to start intruding on other dimensions’ issues when he has plenty of his own to deal with. 

“Well then shut up and let us finish the transmutation. All that shit doesn’t happen on its own, you know.” 

“Brother!” Al reprimands again, but Shouta just nods. 

Putting aside the fact that all this discussion of personal and singular Gates has gone almost entirely over his head, Shouta understands the annoyance of trying to explain something complicated to someone who has no experience. He’d tried a student intern, once. She was well-meaning, and intelligent in class, but not truly cut out for underground work. Shouta does, in retrospect, regret how he’d handled the situation, especially after she burst into tears. At least Nezu hasn’t asked him to do it again. 

So, instead of asking more questions that will eat into the Elrics’ time, Shouta does what he does best: finds a shadowy corner and observes. The corner is not shadowy enough to hide him, but enough that he thinks the Elrics forget he’s there at least some of the time. Good enough. 

Slowly, the blank areas of the circle begin to fill in. When the brothers have their backs turned, and thus forget about Shouta’s presence, they have a few small disagreements. From what Shouta can gather, Al is intent on “shoring up” everything redundantly, and Ed merely thinks it will drain extra energy, but doesn’t seem too offended by the extra safety. (Shouta, personally, is alright with less-than-perfect efficiency if it’s effective and defends him from being–in Ed’s words– pulverized.) 

When Al remembers that Shouta is there, he offers again to have Shouta moved to a more comfortable waiting area— not the holding cell, he promises— and Shouta declines. Whether he understands it or not, he feels better about using this transmutation to get home if he’s seen it constructed with his own two eyes. It’s probably just illogical paranoia. It’s not like he knows what any of the lines and symbols mean. 

Whatever the case, Shouta waits.

Notes:

Aizawa's recollection of advanced technology appearing to be magic is a reference to Clarke's Three Laws.

Sup. This is just a quick scene that was floating around in my head. I usually don't really go for crossovers, but I wanted to get this one written. I don't have a fleshed out world or plot or anything here, just know that Eraserhead gets back home just fine and has a crazy story to tell to his students and friends.
(And he might have some additional reference when he... well.. I said no spoilers in the tags. Let's just say if you know what he and Ed will have in common, you know.)