Archive of Our Own

Eggman should really stop attacking random villages. In a perfect world, he shouldn’t be attacking occupied locations at all, but it feels especially cruel to destroy the lives of people living quietly out in the middle of nowhere.

An Egg Pawn’s gun misses Sonic so badly it might as well have not aimed at all, hitting a building that shudders and crumbles. Tails whacks it in the back of the head with the broken chestplate of its and darts into the air before it can retaliate, nearly swerving into Eggman in his flying orb.

There’s a new addition to the hovercraft. On the side, folded neatly in on itself, is a small laser cannon.

Tails has anticipated it firing for the whole fight, but Eggman’s arsenal has dwindled to the last few bots and it hasn’t made an appearance yet. The sight of its barrel puts him on edge.

When all that’s left is the biggest machine, three times the size of the others, Sonic beckons Tails over. “Gimme a lift!”

They’ve done this enough times that it’s muscle memory— Tails lifts Sonic with both hands and flies up just above the giant robot, then spins rapidly and hurls him at it. Sonic spin-dashes over and over again in speedy succession until the robot lets out a mechanical groan and crumbles.

“That took weeks to build, you stupid rodent!” Eggman roars, raising his fist.

“Um, Eggman?” Tails says, lowering to join Sonic on the ground. “Can I ask you a question?”

Eggman and Sonic wear identical looks of confusion. Yikes. Sometimes it really shows that Sonic grew up around Eggman.

“Make it quick,” Eggman says dismissively, twirling his moustache around one finger. “I’ve got an evil dentist appointment in 20 minutes and I need to get changed. It’s disrespectful to show up covered in grease, you know.”

Tails doesn’t ask what the difference is between an evil dentist and a normal dentist, though the question will probably plague his thoughts tonight. “You know that Sonic isn’t a rodent, right?”

“I’m not? I mean—yeah, I’m not!” Sonic points accusingly at Eggman.

Eggman stares. “What are you talking about?”

“You call him that all the time, but hedgehogs aren’t rodents. They belong to the order Eulipotyphla, not Rodentia.”

“That’s—“ Eggman’s face pinkens to match his nose. “Who cares?! Don’t you have anything better to do than to nitpick over semantics?”

He should just let it go, but a part of him refuses to. “I just think that, after all these years, you could at least call him the right thing.”

Sonic’s eyes flick between them like the audience at a tennis match, his expression a mix of amusement and confusion. He clearly doesn’t give a crap what Eggman calls him, but backs Tails anyway because he’s the best. “Yeah, Eggman, it’s just basic respect,” he tuts.

Eggman snarls with rage, poking around at his console with renewed vigor. “Shut up, both of you! You broke my shiny new machine and then have the nerve to disrespect me!” He hovers his finger over a button, visibly deliberating for a moment before pushing it. “Take this!”

An iridescent glow builds up at the cannon attachment, whirring with a frightening intensity.

“Uh-oh.” Sonic prepares to run, but before he or Tails can speed away a beam of light bursts out and hits them both.

Tails’ whole body vibrates, every cell from his skin to deep in his bones, and he shakes with something that isn’t painful, exactly, but is uncomfortable enough that it might as well be.

For about two seconds.

That’s it. Nothing else happens.

Eggman scratches his head. He looks down at his monitor and back up at them. “Ahem,” he says. “That was… Just a warning! Yes, yes! I’ll be back!”

He zooms away and disappears over the horizon.

Tails looks at Sonic. “… That was definitely supposed to do something, right?”

“Yep. Looks like Egghead messed up somewhere!”

Strange. Something happened, but it doesn’t seem to have harmed either of them. They can both move totally fine. Their memories and cognitive functions are intact. Everything is normal.

Ah, well. Eggman seemed as surprised as they were, so it was probably just a dud.

They head home in search of celebratory street food.

-

Tails has never had a lucid dream before– at least, not until now, since that’s the best explanation for what’s happening.

His surroundings are slightly off. There’s a slight fuzziness to everything, even when he focuses his eyes. And the perspective is all wrong, too— he’s looking down on things that are usually eye height.

What makes him certain that he’s dreaming is looking down and seeing a blue hedgehog’s body.

And he’s ecstatic.

He’s had so many dreams like this! Dreams where he’s Sonic’s real, biological brother- a hedgehog, just like him- and he always wakes up smiling.

Tails darts to the nearest mirror. Walking is unexpectedly clunky and everything happens too fast, but he’ll accept the janky dream physics for a chance to take a look at his hedgehogsona.

His reflection looks just like Sonic.

Which is to be expected, really, given that he’s in a dream world where they’re related, but he thought he’d look a little different. A few hints to his real life form– bigger ears, maybe, or a fluffier muzzle.

He squeezes his eyes shut and tries to customise his face, since he’s heard that you can do stuff like that in lucid dreams, but when his eyes open again, he still looks exactly like Sonic. Unsettlingly identical, really.

When he leans in to get a closer look- which he has to do because his vision is still a little blurry- he can see all the little scars from past injuries and the strands of grey fur that Sonic swears don’t exist and, now that he thinks about it, there is a dull ache in his knees and—

“Hey, bud, you in here?” His own voice calls from the doorway.

Tails turns slowly to face… Himself. Only this other version of himself, hazily lit in the warm morning light, is standing straighter, with more confidence, than he ever has.

“Huh?” Tails squeaks, and it’s Sonic’s voice that comes out of his mouth.

The other Tails grins widely, bizarrely unphased. “Weird, right?” He crosses his arms and leans against the doorway. “Looks like we’ve swapped bodies!”

Tails glances back at the mirror, and Sonic’s horrified face looks back at him. “Oh, no,” he whispers.

“You look great, by the way. I’ve never seen myself in HD before, your eyesight is amazing.”

“No, no, no.” He puts his hands to his face and tugs at the short fur on his cheeks. It hurts and doesn’t wake him up. “No, this can not be happening.”

The other Tails- Sonic, in his body, in real life- laughs awkwardly. “Uh, I’m feeling a little offended, man. What’s so wrong with looking like me?”

Tails has to look down because he’s taller now, and there’s something really unsettling about looking down at Sonic. Almost as unsettling as seeing someone else with his own face. “I can’t be you! I can’t—what if Eggman attacks?” He instinctively reaches to hold one of his tails, but they aren’t there. “I won’t be able to save anyone but everyone will expect me to because they’ll think I’m you and then when I mess everything up they’ll think that it’s your fault and–”

“Hey, hey,” Sonic crosses the room, tripping over the tails halfway, which would have made Tails laugh if he weren’t panicking. He puts his hands on Tails’ shoulders. “Hey, look at me. Or you. Look at you. But I’m you.” Not really helping. “Eggman isn’t attacking right now. We broke a bunch of his stuff yesterday, so he’ll need some time to fix it before he comes back. If he does spring a surprise attack on us, then we’ll deal with it as it comes and we’ll kick his butt.” He says it lightly but with a firmness that invites no questioning. “In the meantime, though,” he points to the two tails hanging limply behind him, “you wanna teach me how to use these?”

-

“You just kinda spin them around really fast,” Tails says, unhelpfully, for probably the fifth time.

They’re in a clearing in the forest near Tails’ workshop.

On the way there, he made his first attempt at running in Sonic’s body and it went about as expected— the movement itself wasn’t hard because his mind already knows how to run and these legs already know how to do it fast, but he’s still adjusting to blurry hedgehog vision and his depth perception is out of whack. That, combined with slower reflexes than Sonic, meant he rarely ran for more than five seconds without hitting a tree.

Meanwhile, Sonic has no experience with tail dexterity and is working from the ground up.

“There’s gotta be more to it,” he grunts, twirling them around clumsily to no effect. Tails has never seen him be bad at something— as if this predicament they’re in wasn’t weird enough. “You gotta have some kinda special technique you ain’t sharing with me, bud.”

It would be cool if Tails had a special technique, but there really isn’t. His tails move as naturally to him as his legs do. Explaining how to use them is like explaining how to walk.

“Maybe it’s like your speed,” he offers. “Like right now, I’ve got the legs but not the quick reaction time you have. I guess you have my tails but not my, um, helicopter skills.”

The concept of himself having skills that Sonic doesn’t have feels laughable, but Sonic nods in agreement like it isn't a stupid idea.

“I will develop helicopter skills,” he says with his usual determination, though the impact is lessened by the strain in his voice from his inelegant flailing. “And you’ll get a hang of running fast, too. Then we’ll be unstoppable!”

“Yeah,” Tails agrees halfheartedly.

-

Night has fallen by the time they wander back. They’ve tired themselves out trying to be each other and their words are punctuated with heavy breaths.

“What do you remember about the thing Eggman fired at us?” Tails asks, his knees aching more with each step. He vaguely remembers that they were hurting when they woke up, but running has sharpened the pain into something difficult to ignore.

(It’s probably his fault. Running into all those trees can’t have been healthy.)

“Not much,” Sonic responds, closing his eyes briefly in recollection. “All I remember is that it was kinda white but kinda every colour at once. And that I’d definitely never seen it before.”

“I hadn’t seen it before, either,” Tails says, though that could have gone unsaid because he hasn’t fought Eggman without Sonic in years. “He seemed to think it hadn’t worked when he fired it at us, so either he doesn’t know what it does or he doesn’t know that it takes a while.”

“We’ll figure it out,” Sonic says, turning from side to side to stretch his back. He leans back and it cracks in multiple places. “You know, my back has been hurting this whole time,” he adds, like an afterthought.

This is the closest he’s come to making a complaint. He’s been freakishly unbothered about this whole thing, even for a guy who is notoriously unbothered about everything. Tails hasn’t noticed the slightest concern about their predicament— although, he supposes, unexpected bodily transformations aren’t exactly a new thing for Sonic.

(Turning into his little bro is probably way better than turning into the Werehog.)

“Huh,” Tails says. “Maybe a side effect?” Come to think of it, he has had almost the exact opposite experience; his spine feels so light and free. He feels supple, like a fish.

“Really? It couldn’t have anything to do with the way you sit curled up all the time?” Sonic teases, jabbing him in the side.

He got him there. “Well, what’s up with these knees?” Tails retorts. “Do they hurt all the time? You never told me about that.”

Sonic suddenly averts his eyes. “It’s not actually that bad,” he says, with no difference in tone but his voice is a fraction quieter. “You’re probably only noticing it because you aren’t used to it.”

“We could get you some knee braces.”

Sonic laughs at him. “Ha! No way. You should really do something about your back, though. This doesn’t feel healthy.”

“Hypocrite!”

“I’m older than you.”

“You don’t act it.”

“Uh, which one of us needs help brushing his tails in the winter?”

“Right now?” Tails deadpans. “You.”

“You got me!” Sonic instinctively reaches to ruffle Tails’ bangs, like he usually does, but he can barely reach Tails’ forehead like this and there are no bangs to ruffle. “We’ll talk about it later, alright, bud?”

‘We’ll talk about it later’ means that they’ll probably never talk about it ever again, which is fine with Tails because he doesn’t want to be peer pressured into correcting his shrimp-like working posture. If it ain’t broke, don’t fix it— his back isn’t broken yet.

-

Whenever there’s something on his mind, it always gets worse at night. It’s one of the reasons why he likes to work late.

The familiar lurch of anxiety hits again as soon as they get home. He wants to get straight to researching to keep his brain occupied, but trying and failing to run like Sonic all afternoon has worn him out.

He thinks he’s acting pretty normal, all things considered, but Sonic doesn’t leave him for the night like usual. Instead, he follows him into the bedroom and perches on the edge of the bed.

“Tell you what.” Sonic pulls out a pen and the instruction manual for Tails’ new Geiger counter, which he flips onto the blank side. “I’ll write you up a cheat sheet, so you can have everything you’ll need to know if Eggman attacked in one place.”

“That would help,” Tails admits, picking up his brush and, remembering that he doesn’t need it, puts it back down again.

Sonic, who looks to be in need of brushing, starts scribbling rapidly. Tails sits next to him and watches, awe gradually shifting into terror as Sonic keeps going, a massive block of text forming on the paper with no paragraph breaks. This goes on for several minutes, and just as it looks like he’s about to run out of space, Sonic’s writing comes to a stop.

He feigns wiping sweat off of his brow. “Yeesh. Had to cut it short towards the end ‘cause I ran out of space, but that should be just about everything.” He slides the paper over. “Here you go. Sorry ‘bout the handwriting.”

Sonic’s handwriting is notoriously dreadful. He has the handwriting of someone who doesn’t know how to read– ironic, considering he reads more than Tails does.

This only makes it harder for Tails to make out what the words say as he strains his unfortunate hedgehog eyes. He slowly mumbles what he can make out. “Egghead, Eggface, Eggbreath, Egg–“ He looks up. “This is just a list of all of your nicknames for Eggman.”

“Yeah,” Sonic says. He points to about halfway through, where ‘Baldy Nosehair’ is written in all caps and underlined several times. “Be sure to remember that one. It’s real funny.”

Baldy Nosehair was funny, once. After the tenth time Sonic said it, not so much. Unfortunately, Tails is an amazing friend and little brother so he laughs enthusiastically every time.

“Um,” Tails says, shifting awkwardly. “Not that I don’t appreciate this or anything, but I was kind of hoping for something a little more… Strategic. Like, attack patterns or something.”

Sonic shrugs. “You already know how to do everything I can do. The only difference is I can do the moves faster, and I look cooler while doing them. But the coolness factor is mostly the speed, and you have that now.”

Sure, Tails knows how to spin-dash and do all the attacks that Sonic can do- he learned from the best, after all- but he’s nowhere as skilled as Sonic is. He can’t handle a horde of Badniks single handedly like Sonic can.

“Actually,” Sonic adds, seeming to pick up Tails’ hesitation, “no, there’s another difference. I do everything with a lot more confidence than you do. Most of knowing what you’re doing is just looking like you know what you’re doing, you know?” He strikes an exaggeratedly confident pose. “So, seriously, you already know everything you’ll need to know, but if you ever feel unsure,” he taps his finger on the sheet of nicknames, “just call him one of these. It’ll distract him long enough to let you think of something.”

Tails looks uneasily at the sheet of egg-related nicknames.

"Actually," Sonic says again, louder and more eager this time. "I forgot something. There is one piece of real, practical advice I can give you.” He puts his hands together and speaks very seriously. “If you really gotta pee during a fight, ask someone to cover you for a sec and then after you’ve done your business, give them a look like this,” he shrugs, turning his head in a subtle shake. “They’ll think you had a secret plan that didn’t work, and then the fight can continue as normal.”

“… That’s what it means when you do that?”

“What’re you looking at me like that for? It’s hard to hold it when you’re running and jumping around.” A brief pause. “Sometimes I really do just have secret plans that don’t work, though.”

Tails takes the pen and squishes a tiny note onto the bottom of the sheet of nicknames. While this still isn’t the kind of advice he was hoping for, it's undeniably a problem he could potentially run into. “Okay,” he says, clicking the pen a few times, “and what if there’s nobody to cover me?”

“In that case, you just gotta be really fast and hope that nothing extreme happens in the ten seconds that you’re gone. If Eggman asks where you went, just tell him you went on a speed date with his mom or something. Then the fight carries on as normal.”

Sonic recites the scenario with so little thought that it must have happened before.

“But that’s it, for real this time. I got nothin’ else.”

Tails waits for another ‘actually’, just in case.

“Nothing’s gonna happen, but even if something did, you’d do great,” Sonic says, ruffling Tails’ bang-less forehead. “I’m not just saying it to make you feel better. I really mean it.”

“Okay.”

Alone in the darkness, Tails discovers that his bed is now too small. His feet stick out at the bottom if he lays flat on his back, so he curls up like hedgehogs do.

-

Mysterious and unexplainable happenings inflicted by Eggman are usually caused either by an ancient deity of some kind, like Chaos or Dark Gaia, or a powerful stone, like the Phantom Ruby and Warp Topaz.

For his own mental wellbeing, Tails chooses to believe that Eggman has run out of borderline-invincible beings to try and recruit to his side, so he aims his research towards crystals and spends the morning falling down an internet rabbit hole. It’s weird to work without his special juice, but he isn’t sure how Sonic’s body would react to it so he sips intermittently on a soda instead.

Some are clearly made up, others seem like they could plausibly exist, but only as afternoon creeps in does Tails find something useful.

The Spirit Opal. Every account he can find lacks detail or a credible source, but they all say about the same thing: it seems to transfer one’s consciousness- their ‘spirit’- from its existing host to another.

Body swapping, in other words.

There’s so little documentation that Tails isn’t even sure it exists, but it’s the best lead he has.

After at least fifteen minutes of being unable to locate more data, Tails is saved from his uneventful search by the swinging open of the workshop door.

“You gotta help me, man,” Sonic laments with exaggerated despair, though there’s an undercurrent of real stress in his words. “People keep asking me to fix their stuff and I only know how to fix planes. I don’t think pocket watches work the same way planes do.”

“Planes and pocket watches are not the same,” Tails agrees wisely.

Sonic swings his knapsack over onto the table with a thud. “I had no idea so many people knew you’d be able to fix their stuff.”

“Well,” Tails says, shrugging a little, “a couple years ago I started repairing people’s stuff to pass the time when I didn't have a big project, and now everyone who lives near one of my workshops knows about it.”

“I didn’t know you were taking on extra work. If you needed help paying your taxes or whatever, I could have helped.”

Tails furrows his brow. Sonic has misunderstood him and also, for what it’s worth, doesn’t even know how to file taxes. “It’s not a job. I just help people sometimes.”

“But they pay you, right?”

He doesn’t say anything.

“They pay you. Right?” Sonic repeats slowly. There’s an intensity in his eyes that doesn’t look right on Tails’ face.

“Why would they?”

“Uh, because you’re doing them a service? They’d pay a plumber, wouldn’t they?”

“It’s not the same.”

“Tails, I went to the store to buy hotdog buns and on the way there and back I accumulated two pocket watches, a wrist watch, and a phone.” He pulls each thing out of the bag as he talks, finishing with a modern smartphone. “This is a phone, right? I’m not actually sure.”

“It is,” Tails confirms. “They keep getting thinner, don’t they? It’s weird—“

“No changing the subject!” Sonic tuts at him. “It’s gonna take you hours to fix this stuff!”

“It doesn’t take that long,” Tails mutters defensively. Even in the bigger body, he still feels small. “It’s literally not a big deal, I just like helping people.”

Sonic looks at him for a few seconds, his oversized ears slowly drooping. “I’m not mad, bud,” he says, his voice quieter. “I’m real proud that you’ve been helping people out. I just don’t think you should be doing this much without any compensation.”

It doesn’t seem fair for Tails to demand payment for this when he can do most engineering work as absent-mindedly as he could eat a bowl of cereal.

(If anything, he’d have more issues with the cereal because engineering doesn’t pose the risk of spilled milk. Just electrocution, which doesn’t require cleaning up, and is therefore simpler to deal with.)

He mumbles something in vague affirmation and, thankfully, Sonic drops the subject. “… You’re right about those phones,” he offers. “They really are getting thinner. They’re like panes of glass.”

-

“I think you might be comin’ down with a cold or something,” he says a few hours later, scrolling through the document Tails composed of every testimony on the Spirit Opal he could find. “Just to warn ya.”

“Aw.” Tails sits across from him, adjusting the screws on a pocket watch.

“Yeah. I’ve been real fatigued and I got a killer headache. No sniffles yet, though.”

Tails opens his mouth and then he closes it. “Oh. Uh. Um.” He nibbles nervously at the handle of his screwdriver, which doesn’t feel as good without his own teeth.

“What?”

“I might know why.”

“What is it?”

“Do you promise not to get mad?”

“Why’d I be mad?”

Tails opens a secret compartment under his desk and retrieves an innocuous juice box. He hands it to Sonic. “Drink this.”

“Your special juice? Heh, don’t tell me you secretly have a deadly disease and the special juice keeps it at bay.”

“Something like that,” Tails says darkly.

“Ohhkay…” Sonic puts the straw to his mouth and takes a tentative sip. And then nearly gags. “Wh—ugh! Is this coffee?!”

Tails nods sheepishly. “I think you’re going through caffeine withdrawal.”

“Since when have you been drinking coffee? And why is it in a juice box? This isn’t juice!”

“It’s bean juice!” Tails argues. “It’s been… A while. I put it in juice boxes so you don’t know what it is.” And also because it's fun. He has a tiny funnel. “I know you always say you didn’t want me drinking coffee but, look, I pull a lot of all-nighters.”

Sonic glowers at the juice box like it insulted him. “I don’t wanna drink this. It tastes like dirt.”

Tails takes his coffee black because he is a sophisticated young man. “You can put milk and sugar in it,” he offers.

“I don’t think anything can make this taste good,” Sonic says, but he heads into the kitchen anyway. In the doorway, he puts two fingers to his eyes and then points them at Tails. “We’re talking about this later.”

-

Out of all of the changes that have come from inhabiting Sonic’s body, the one thing that Tails actually really enjoys is the ability to go wherever he wants within hours— even minutes, if it’s close enough.

Running helps burn off some steam in a way that flying doesn’t quite achieve- it’s a full-body movement, so it tires him out more- and the change of scenery is nice. It almost keeps his mind off of things.

Maybe it’d be a better distraction if people didn’t instantly recognise Sonic.

Most leave him be: they glance past him, do a double-take, stare a bit, and then go on with their day with little more than a wave or a nod of acknowledgement. It’s unobtrusive enough that he can almost ignore the prickly feeling of constantly being watched.

And then there are the super-fans who run up to him, ask for a selfie, and tell him that they’ve been tracking him ever since the Station Square incident. One at a time is mostly harmless, albeit pretty scary, but once a small crowd forms, Tails starts panicking.

Thankfully, Sonic doesn’t like too much attention, either, so it’s perfectly in character to randomly blurt “gotta blast!” and zoom the heck out of there.

But he can’t seamlessly escape everyone.

“Sonic!”

He turns around slowly, infinitely glad that Amy doesn’t surprise hug Sonic every time they cross paths anymore, and adopts what he hopes is the correct smile.

“Hey, Ames,” he says, scratching the back of his neck like Sonic does.

This is dangerous territory– Tails has watched Sonic shrug off affection from Amy for years, but that’s only how he behaves with an audience. How does he act around her in private?

All of this worrying about ruining Sonic’s reputation and Tails never considered the possibility of ruining his love life.

(If it even is his love life. Usually, Tails appreciates that Sonic doesn’t tell him about any mushy stuff, but right now he wishes he'd divulged at least a little bit.)

“What are you doing here?” She asks, swaying side to side like a cheerful flower in the breeze.

“Not much.” He aims for casual, but he fears he overdoes it and comes across as uninterested instead. He tries to salvage the moment with a question. “What about you?”

She holds up a paper bag with a giant crusty baguette sticking out of it. “The bakery a few streets over is so good. I know it’s weird to travel so far for bread, but it’s worth it. Their sourdough starter is two hundred years old!” She sniffs the baguette like she can smell the two hundred years of yeast. “Do you want to try some? I picked up some cute pastries as well. We could have a picnic!”

Tails winces at the prospect of a romantic picnic with Amy. “Oh, uh, I, uh,” he scrambles, “I actually just ate.”

Amy’s ears droop a fraction, but her expression is otherwise unchanged. “Ah, okay. Maybe some other time, then?”

“Probably…?” He’s doing a horrible job at being Sonic. Amy has totally thrown him off.

She gives him a searching look, her eyes scanning him from head to toe. “Are you okay? You’re standing weird.”

“I’m not standing weird,” he says quickly.

“You are! Your shoulders are so tense.” She deliberates for a second, and then laughs. “You’re standing like Tails! You know the way he hunches over. You two are so alike sometimes.”

Tails doesn’t hunch over. He stands normally. She doesn’t know what he’s talking about.

Technically, there's nothing stopping him from telling her what happened– there’s nobody else around and he trusts her not to tell. It’s just that he’s never had to tell someone that he isn’t Sonic before and, besides, the conversation has gone on for long enough that she might feel misled.

In his uncertainty, he says nothing.

Amy sighs at his silence. “You know I’m here if you need to talk about anything going on with you guys,” she says earnestly, looking up at him with frightening sentimentality.

That's a weird thing to say. “What?”

“Come on,” she says, like this is a well-trodden topic of conversation. “If you won’t talk to each other, you should at least talk to someone.”

“We talk to each other,” he argues instinctively.

“Really? Told him about the nightmares yet?”

Something uncomfortable curls in Tails’ stomach, not only with worry but also at the thought that he wouldn’t be the first person to know about Sonic having nightmares. He can only stare.

She sighs again, wearing a weary expression that he has never seen her look at Sonic with. “Take care, okay?” She takes his hand and squeezes it for just a second, letting go before he can decide how Sonic would react.

“Sure, yeah,” he says, dazed. “Uh, I gotta go. See ya.” He speeds away and her goodbye dissipates in the wind.

-

Tails needs answers. He doesn’t want answers, but he needs them.

He finds Sonic lazing around in the grass. “Are you and Amy dating?”

Sonic startles cartoonishly— that is, to say, even more cartoonishly than usual. “Whuh?” His fur puffs out everywhere, and Tails now understands why people say he looks cute when he’s scared.

“Are you?” Tails taps his foot expectantly. He doesn’t usually tap his foot, but there’s something about being in Sonic’s body that makes the movement feel natural.

Sonic pulls himself up to a sitting position, leaning back against both arms. “You really wanna know?”

Not at all. “It’s been long enough.”

“You won’t like the answer.”

Tails can feel his internal organs dissolving from the sheer force of cringe, but he persists, sitting down in the grass. “That’s fine, I just need to know the truth.”

“I dunno.”

“... What?”

“That’s your answer.”

Tails gawks. “You don’t even know? Well, do you like her?”

“Dunno.” A smirk forms, but it’s not the kind of smirk he does when he’s lying.

He was right. Tails doesn’t like it. “How can you not know if you like someone?” He throws his hands out in frustration.

It’s not as if Sonic lacks an understanding of those kinds of feelings; Tails has seen the romance novels that he pretends aren’t under his bed.

“I’ve just never really thought about it.” Sonic laughs shamelessly at Tails’ expression and generously offers a mediocre explanation. “I didn’t like it when she wanted to marry me because I don’t wanna get married, but that's not a thing anymore. I just like hanging out with her. I’m not gonna waste time wondering why or how.”

Another thing that Sonic and Eggman have in common: they are both prone to unexpected stupidity.

“Well,” Tails says, feeling like he has gained more questions than answers from this conversation, “you have to schedule a picnic date with her when she’s back in town.”

“Cool.”

He didn't plan on bringing it up, but he can't help but remember conversation with Amy, the part that he’s been trying very hard not to think about. He tends to suppress any awkward interpersonal issues as much as possible because it’s easier to ignore it than to bring it up.

(And also because that’s how things are with Sonic. If something isn’t life-threatening, you move on. Everything is fine.)

He suddenly feels the need to do something with his hands so he rubs them together, feeling the texture of the gloves. Sonic’s gloves are thinner than his own and therefore less resistant to burns, but they’re also more comfortable. “And she said that she’s here if you need to talk about anything.”

“I know,” he says cheerfully. “I never do.”

“Do you?” The words come out involuntarily.

“Whuh?”

“Amy said something about nightmares.” It feels like he has to force the words out. It’s a transition into a conversation that he can’t remember ever having with Sonic, an attempt to poke at the person behind the persona.

Sonic groans with more agony than he’d usually express after a severe injury. “She wasn’t meant to know about that. I accidentally slipped that I hadn’t been sleeping well and then she kept asking all of these questions until I told her. She was insisting I should see a doctor about sleep apnea, and she said she’d book my appointment and go with me.”

Not even envisioning Sonic with one of those anti-snoring sleep masks can lighten the mood right now. “Why didn’t I know?”

“It’s literally not a big deal.”

“If it’s messing with your sleep, it’s a big deal.”

Another ragged huff. “It’s not some secret representation of inner turmoil or whatever. It's just that sometimes after real intense bad stuff happens, my brain kinda replays it in my dreams for a while, but I usually forget about it once I’ve been awake for a few minutes so there’s no reason to bring it up.”

“Intense bad stuff?”

“Yeah, y’know, like the- the Infinite thing. And watching a guy die in space was kinda a bummer so I had them after the ARK thing.”

“I had nightmares after the ARK.” He'd forgotten about that until now.

“What?” Sonic sits up completely.

“Not about Shadow,” he says, like that makes any difference. “About you. I know it was different for us on the ship, but we thought we’d just watched a guy die in space, too.”

“Oh. Wow, man, I’d never thought about it like that.”

“You thought I’d just be fine after watching you get ejected into space?”

“You seemed fine.”

“So did you!”

They fall into a part-concerned part-sulky silence.

Slowly, Sonic lays back down. “Sorry about that, bud. I should’ve been checking in with you. You go through a lot for your age.”

“You go through a lot for your age.”

“But I’m fine.”

“Sonic.”

“Okay, okay, it’s not fun when bad things happen. Dreaming about it is probably– Amy said it could be my brain processing stuff. I guess sometimes I need to ‘process things’.”

“You don’t have to do that on your own.” ‘And,’ his mind supplies ‘neither do I’.

A pause. “C’mere.”

Tails lays down on the grass and Sonic snakes an arm around him, swiftly dodging the quills, and pulls him in. His hedgehog spine instinctively curls up and he rests his head on Sonic’s arm.

It would have been cool if he was in his own body and it didn’t feel like he was getting hugged by himself, but he’ll take what he can get.

“I think I did a pretty good job overall of the whole ‘raising a kid while being a slightly older kid’ thing. Might’ve messed a few things up, though,” Sonic says, his borrowed voice a little quieter. "Sorry 'bout that."

“You did great.”

“Yeah, you turned out pretty awesome.”

Tails doesn’t think Sonic should take all of the credit for his awesomeness, but he lets it slide for now. “I guess I'd have liked it if you acted more like a real person when it was just us two.”

“Calling me not a real person? Ouch.” It’s a joke, but with no real laugh behind it. It’s a joke for the sake of telling a joke during an awkward moment.

“You know what I mean.” No response– he does. “If you never talk about being sad or scared, then I don’t want to because it makes me feel like a burden.”

“You’re never a burden, buddy.” Sonic tilts his head in and rubs Tails on the arm.

“You should tell me if you’re doing bad," he insists. "You don’t have to go into detail, but I wanna know how you’re doing and if I can help.”

Sonic makes a vague noise of assent.

“For real,” Tails says, poking Sonic in the spot on his stomach that really tickles. Sonic yelps, shrinking in to protect himself. “I won’t talk about things if you don’t.”

“Okay, fine.” They watch the sky for a while until Sonic huffs, with the exasperation of someone that has been holding back a complaint for a long time, “I can’t believe your special juice has been coffee this whole time! I don’t wanna be drinking that, it’s gonna be my next nightmare fuel.” A pause. “Is it okay if I joke about it? I think it’s gonna be way easier if I can make jokes.”

“If you start having coffee nightmares, just let me know,” Tails deadpans, and they share a private laugh.

-

It’s a beautiful beach, the kind where the sand is white and the sea is a bright, clear blue. Distant palm trees sway gently in the salty breeze and, through these blurry eyes, everything smudges together like an oil painting.

He’s taking a Sonic-style nap, flat on the sand with his arms folded behind his head. It took a while to arrange the quills so that he isn’t getting stabbed, but he made it work.

It’s peaceful. He can hear the waves, distant enough that he doesn’t have to worry about the tide coming in, lapping against the shore.

He knows as much about the Spirit Opal as he possibly can. He’s studied blood, fur, and quill samples as closely as he could and found nothing out of the usual. All there’s left to do without the Opal itself to work with is run a bunch of increasingly esoteric experiments until he finds something to work with.

He’ll head back soon and get things started.

There’s a rumbling beneath him, like the ground itself is telling him to get on with it. He didn’t think this area was prone to earthquakes.

Unless it isn’t an earthquake. The vibrations are concentrated in one spot and increasing in intensity, almost as if something large is pushing its way up through the sand. Almost like—

A giant metal claw erupts out, scattering sand and crabs as it careens into the air and makes its way straight for Tails.

His tails spin at max speed to get him off the ground and out of the way in time.

Or, they would if he still had them.

That moment of stagnation, of forgetting that he’s Sonic and Sonic needs to run, is all it takes for the claw to effortlessly sweep him up into its clutches. He thrashes and fights, but there’s no escaping.

From another patch of land, Eggman bursts out in his hovercraft. His muffled cackles are loud, even behind the safety glass. “Well, well. Look who it is! Sonic the Hedgehog!”

“What do you want, Eggman?” Tails hollers, pushing the terror back down his throat.

Sonic wouldn’t be afraid in a situation like this. He’d be laughing and joking and making comments about the lack of originality. A metal claw, really? I thought you retired those years ago, doctor.

“What do I want? Hmm…” Eggman scratches at his chin in a mockery of thoughtfulness. “Your last words would be good. I’ll record them so I can listen to your final moments when I need a pick-me-up.”

Uh-oh. Sonic didn’t say anything about last words. “In that case, uh… Eggface, I won’t say anything!”

Eggman's moustache droops, unimpressed. “Ugh. Those are terrible last words. Before I kill you, I'll have to torture you until you say something interesting.”

Tails gulps.

The claw extends suddenly, pulling Tails over the ocean as Eggman hovers alongside him, mumbling to himself about which forms of torture are currently accessible.

Once the shore is barely visible and Tails is surrounded on all sides by the endless ocean, the claw stops. They’re so far from land even if somebody were on the beach and saw what was happening, they couldn’t possibly get here in time to save him. It’s just him, Eggman, and miles of sea.

“Ah, Sonic the Hedgehog. The blue thorn in my side, the annoying animal that has consistently gotten in my way for so many years. We have such a long history together,” Eggman laments, though there’s no real emotion to it. It’s like he’s performing a funeral scene in a play while thinking about what he’ll eat later. “It’s almost a shame to end it all so abruptly.”

What would Sonic say? “It isn’t over yet, Baldy Nosehair!”

Eggman carries on, taking little notice. Maybe this monologue really is scripted. “It’s about time I got rid of you. I could have done it all those years ago if I had been smarter, if I’d done it the obvious way instead of trying to give you an entertaining end— an end that you don’t really deserve, don’t you think? No, it’s time I ended this.” His voice takes a dark, sinister turn.

“You’re doing a whole lotta talking and none of that torture you promised,” Tails gasps, fighting for breath against the grip of the claw.

Again, he’s ignored. If he weren’t moments from death, he’d be annoyed that Eggman isn’t taking any notice of his Sonic impression.

“You thought you’d kept it a secret from me. That, somehow, I didn’t know about your biggest flaw. The one thing that you can’t do.”

Wait a second. They’re over water. Eggman intentionally brought him here, not because it’s isolated but because—

Eggman smiles menacingly, showing all of his blunt, white teeth. “You. Can’t. Swim.”

Tails lowers his head and turns his face away, in case the relief shows on his face.

“I’m going to let go of you and you’ll sink to the bottom of the ocean like a rock. Nobody will know what happened to you. Nobody will find your body. You’ll disappear forever. So, I’ll prompt you again: What are your last words?”

Tails looks up and stares defiantly into the face of a man who thinks he has finally won. “Gotta go fast.”

“Still mediocre, but it’ll have to do. Goodbye.”

The claw releases and Tails plummets into the freezing ocean.

His limbs want to seize up but he won’t let them– especially since they’re not even his own. The body he’s occupying is borrowed, and the least he can do is swim it to safety after getting it into this mess in the first place.

He kicks as hard as he can to propel himself back up to the surface, but it’s clumsy and difficult. These legs only know how to run, and it occurs to Tails that just because he knows how to swim doesn’t mean Sonic’s body is able to.

The surface doesn’t look any closer. He doesn’t seem to be moving anywhere, just flailing underwater.

It’s over. He isn’t going to make it and Sonic will be stuck forever in a slow, useless body that doesn’t even belong to him.

“I’m sorry, Sonic,” he tries to say, but it comes out as bubbles.

But then– Air! He’s alive!

Tails coughs and splutters in air that’s no warmer than the sea. His salt-stung vision is hazy and waves are crashing in his ears. He has no idea where Eggman is, but must still be nearby; he wouldn’t kill his greatest nemesis and head straight back home.

Frantically, he spins around until he detects land and heads straight for it.

Swimming is easier now that he can breathe, but not by much. His muscles are cramping up from the foreign movement and the wet chill, and it’s only through strength of will that he keeps moving.

It’s hard and it hurts but he does it. He swims and swims and swims, hope growing in his chest as the land gets gradually closer until finally he flops, inelegantly, onto sand and rocks. Retching up more seawater, he thinks deliriously that he's never been so glad to get sand in his fur.

Eggman is already there, parked in mid-air and watching Tails stagger to his feet and attempt a heroic, Sonic-esque pose.

They stare at each other.

Eggman’s moustache ruffles as he sighs, his shoulders slumping. “What are you, then? Some kind of shapeshifter?”

“Huh? No, I’m—“ Tails realises with inappropriate excitement that he gets to say the line. “I’m Sonic, Sonic the Hedgehog!” He rasps through his scratched throat, jabbing his thumb smugly at his chest.

“Obviously you aren’t,” Eggman snarks, unimpressed. “You just swam to shore.”

“Obviously, I learned to swim. Eggface.”

“Sonic will never learn how to swim because making the decision to learn how to do something would involve acknowledging that he couldn’t do it in the first place.” He makes a dismissive, swatting gesture in Tails’ direction. “Drop the act. Now I think about it, I should have known something was wrong when you looked afraid before I dropped you in the ocean. The rodent always appears excited in the face of danger.”

“He’s not a rodent—!“ Tails slaps a (wet, sandy, disgusting) glove over his mouth, but it’s too late.

“Aha!” Eggman hovers further down so that the belly of the orb brushes against the sand and, when he extends a taunting finger, it’s almost within biting distance. “I know it’s you, fox boy. You can’t hide from me.”

Bold of him to act like he figured it out all by himself when Tails gave himself away.

“It was the Spirit Opal, then? It must have had a delayed reaction. Here I was thinking it hadn’t worked.” He sighs dramatically. “Do you have any idea how much time I've spent in the lab trying to figure out what was wrong with it?! You should have told me!”

“Yes, Eggman, I should have told you that the weapon you used against us actually worked, so you’d save time trying to destroy the world or whatever.“ Tails rolls his eyes, which, in Sonic cosplay, feels cooler than usual.

“Exactly! Wait— don’t get cocky with me, boy! I like you better when you’re scared.”

Tails is still as terrified as he was when he first got captured, but he can talk back and be scared at the same time. He does all kinds of stuff while scared. Heck, he does most stuff while scared.

He can also think while scared, and what he’s currently thinking about is how close the laser attachment is now that the orb is no longer in flight.

“You haven’t given me anything to be scared of,” he lies, and, before Eggman can retaliate, he curls into a ball and launches himself up.

The orb makes a satisfying CRACK upon impact, jolting backwards and prompting an undignified scream from the occupant. Immediately, the floating mechanism kicks back in and it whirrs, rising back into the air.

“That was uncalled for!” Eggman shouts, even though every attack against him ever has been extremely called for.

Tails spin-dashes into the orb again, but it flies out of reach before he can hit it another time. The chassis is dented near the front and the laser attachment is dangling by a few wires, exposing the round, iridescent crystal within.

Now out of harm’s way, Eggman does some fiddling with the controls, yelling irrelevant insults that Tails doesn’t bother to dignify with a response. An older, more familiar cannon erupts from the side to shoot fireballs as some low-tier badniks emerge from the sand.

Clearly, Eggman hadn’t prepared for much of a fight if all that he has are a bunch of Motobugs. Tails stomps on them with ease, just as he’s done ever since he was a little kid. Even the fireballs aren’t difficult to dodge, though he has to be careful to avoid the patches of bubbling glass that have already been hit.

The whole time he’s inhabited Sonic’s body, he’s taken being unable to fly pretty well. It had only been a minor inconvenience until this moment, in which Eggman would be easily accessible if only he wasn’t trapped on the ground.

Tails wants his body back for a new reason— not out of fear of filling Sonic’s shoes or of wanting the comfort of the familiar, but for what it can do. What he can do.

He’ll just have to do it Sonic’s way. He scans the environment for something to propel himself off of, stumbling over a crushed Motobug (sturdy, but not tall enough) in his distraction.

“You’re even weaker than usual with those borrowed legs,” Eggman heckles. “I could destroy you now if I wanted, but you want to run home to Sonic, won’t you? Go on, lead me to him. I’d like to see him fare against me without his speed.”

Eggman, distracted by his own words as per usual, doesn’t notice that Tails has been luring him towards the palm trees further up the beach.

He knows how to do wall jumps only in theory. He’s watched Sonic do it countless times but, since he can usually fly, has never attempted it himself. Thankfully, he has a lot of experience running into things as of late, and the head injuries haven’t even been all that bad.

He dashes towards the tree, leaping into the air and jumping again just as his feet come into contact with the trunk. In the fraction of a second it takes to come into contact with Eggman’s flying orb he curls into a ball.

The resulting CRACK is the most satisfying of all.

Tails lands inelegantly on his butt. The hovercraft, having taken three hits (which, as always is the amount of hits it takes to destroy it) is falling apart and raining scrap metal. Eggman is alternating between yelling and violently hacking from inhaling the smoke.

The laser at the front has broken off entirely and the Opal is still attached, but loose. All it takes is a thrown coconut and it slips free down onto the sand.

Tails should really run some tests before touching it directly, but there’s no time. He hopes, as he grasps it, that his gloves will be enough protection.

So far so good. “Pleasure doing business with you!” He salutes Eggman, though the human seems too busy fighting for his life in a combusting hovercraft to notice.

And then, just as Sonic would, he shoves the gemstone in his quills and makes a run for it.

-

“Whoa, bud, what happened?” Sonic freezes in the motion of lifting a half-eaten chilli dog to his mouth (they don’t taste as good with Tails’ taste buds, as he keeps complaining, but that won’t stop him from eating them.)

Tails leans against the doorway as he rummages around in his quills for the Spirit Opal. “Eggman happened.”

Sonic nods sympathetically. “Ah, yeah, he happens a lot. You okay?”

“He tried to drown me.” He’s still looking.

“Dang, that would’ve actually worked if it was really me. Lucky!” Sonic resumes his ‘dog, nonchalant as always about avoiding death by sheer chance.

Tails can’t find the Opal. “Um, be right back.”

“You just got h—“ He doesn’t hear the rest.

Cool that he gets to be the one vanishing mid-conversation for a change. Not so cool that it’s because he lost a rare, powerful item that is their only hope for switching their bodies back.

It turns out the Opal fell out of his quills a few miles from home, so he doesn’t have to run around the planet looking for it. Thank Chaos for that— if he ran into Eggman a second time, he’s not sure he’d get out of it so easy.

“That was rude,” Sonic remarks upon his return.

“You do it all the time!”

“That’s different.”

“How is it different?”

“Just is.”

Tails reaches out to his quills to pull out the Opal, which he put back before he walked in so he could pretend that it had been there the whole time. “Anyway, I got this."

-

The plan is to put the Spirit Opal into a laser cannon, reverse the polarity, and fire the laser at themselves.

Tails does this by inserting it the wrong way around. ‘Reversing the polarity’ is just an elaborate way to say making something go backwards and he likes to say it because it makes him sound smart, which is even more satisfying than actually being smart.

The setup is similar to those huge, old fashioned portrait cameras. He gets everything in place and makes sure the angle is right, then turns on the timer and joins Sonic on the insulated panel where the laser will fire.

“What are the chances that this’ll just blow us up?” Sonic asks conversationally.

“Very low.”

“But not impossible?”

“With this kinda stuff, there’s always a miniscule probability of a horrible explosion.”

“Cool.”

Other than the poor eyesight, the aching knees, and the horrible fear of failing to save the world, being Sonic hasn’t been so bad.

There’s a reason he runs so much even when he doesn’t need to; going super fast is awesome. Running at top speed made Tails feel untouchable, intangible, for those five-ish seconds he could last until he ran into something.

Tails gets one last look at Sonic— as himself, through Sonic’s eyes. He sees something small and fluffy with huge ears. He knew he was small and fluffy, but he never realised how big his ears were until now.

He can’t wait to be small and fluffy (and have big ears) again.

The cannon whirrs unsettlingly before it fires and, talk about deja vu— everything about it is the same. The same light, the same intensity. The same feeling of an unknown process having occurred and the same nothingness afterwards.

“Looking promising,” Tails says, still in Sonic’s body and expecting no different.

Since the transformation happened during the night last time, they planned to pull an all-nighter in the hopes of catching it as it happens.

You know, for science reasons. The online information about the Spirit Opal lacked any stats or detailed accounts, so Tails wants to take some notes and publish a paper about it for clout within the science community.

There’s a chilli dog slowly cooling on the countertop. Tails reasoned that it’d be better to prepare it when they swap back so that it won’t be cold, but Sonic said that he wants a bite of (potentially room temperature) chilli goodness to be the very first experience he has when he gets his body back.

Tails wants his first experience with his body back to be running his hands through the fur on his tails. He could do that while they’re still swapped, but it’s not the same if the tails aren’t on his body. And also it would be awkward because he’d be touching Sonic.

He starts feeling something weird. A numbness, starting in his fingertips that slowly progresses up his arms and through the rest of his body.

(Sonic's body. But not for long.)

"Woah," mutters Sonic, beside him. "You feelin' this, bud?"

Tails nods. "Yeah. Really weird." He wishes he could take notes but he can't feel his hands anymore.

He's frozen in place, which makes him panic, but the anxiety dissipates as abruptly as it comes and gives way to an out-of-body nothingness. He can see himself, sitting on the couch with Sonic, from a birds-eye view, but it doesn’t feel weird. It’s like how wacky stuff happens in dreams and, in the moment, it feels completely normal.

And then he wakes up. He must have fallen asleep while waiting for their bodies to swap back. He can’t wait to get back into drinking his special juice so his body will stop surrendering to sleep without his permission.

He runs a sleepy hand through his bangs and—

Wait.

He does it again. His bangs are back!

He leaps up onto his feet- which are his feet!- and stretches his legs- which are his legs!

Ow. His back. Maybe Sonic had a point.

In unison, they jump up and shout with triumph, hug each other with the right bodies this time.

-

A goat lady waves at Tails from across the street. He recognises her face but can’t pinpoint from where, which means that either he helped Sonic rescue her from an Eggman attack or he’s been repairing her gadgets.

“Mr. Prower!” She greets as she crosses the road. She stands before him, rummaging around in her purse before holding out a stack of rings. “Here’s what I owe you. This should cover the watch, as well as the camera you repaired last year.”

Tails blinks up at her. He’s never been presented with so many rings at once before. “Huh? You don’t need to—“

“No, you were right yesterday.” Yesterday? “I should have been paying you this whole time, but you never asked and it always slipped my mind.” She insistently pushes the rings into Tails’ hand.

What has Sonic been saying to people?

He totally should have asked, but Tails can’t be mad at Sonic for doing the hard part for him, not really. He closes his fingers over the rings. “Thank you,” he says.

“No problem,” the goat lady says. “I’m glad you’re giving yourself the credit you deserve. You’re like a local celebrity, you know. Everyone talks about the fox boy that can fix everything,” she adds with a little laugh.

They bid each other farewell and she returns to the other side of the street. Tails runs his thumb over the rings and allows himself, though it’s hard, to feel like he deserves them.