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⸻
The world had never been in as much danger as it was in that moment.
At least Sonic’s world certainly was.
The embarrassment was mounting as the G.U.N. doctor continued to run tests on his new physical form.
“Information for the Mobian database,” she had said.
For Sonic, it was just all very, very, very embarrassing.
Who knew Mobians reached adulthood in just a few months?!
Certainly not Sonic, but when he turned eighteen, the transformation hit.
For humans, it’s slow and gradual—not for them.
Two months of excruciating muscle pain, spine aches, even tooth replacement.
He had grown taller, his fur darker and shinier, his teeth sharper and stronger, his muscles more defined and powerful.
A full-grown adult.
Incredible.
“Your parameters are excellent—your muscle mass has increased by almost thirty percent! Shadow’s is over forty, but his genes from Black Doom affected things differently and—”
He wasn’t listening anymore.
Shadow.
Shadow had become even more dangerous—and even more stunning.
He wouldn’t have believed it possible unless he’d seen it with his own eyes.
His bones had practically vibrated when he saw him last week, after the development phase that apparently hit Shadow at the same time.
His heart pounded just thinking about it.
And the electrodes taped to his chest recorded it immediately—the furious beating that flared just from remembering Shadow—now taller than him, muscles even more toned, fur black and red with such vivid contrast it almost hurt to look, and those fire-red eyes brighter than ever.
The teeth—those damn fangs—and… OH GOD.
As if it wasn’t hard enough already, right?
Admitting to himself some time ago that he had feelings—uncontrollable ones—for that damned hedgehog.
This just made it worse.
“Sonic, are you okay?”
The doctor had stopped her rambling, alarmed by the sudden spike in the blue hero’s heartbeat.
Perfect. Great. What a-
“Yes, it just makes me a little nervous, all this. It’s weird.”
He lied easily, still surprised by his new voice.
That had changed too.
Not drastically, but less high-pitched—deeper.
Shadow’s voice had become even raspier.
It twisted Sonic’s insides in… too many ways.
“Don’t worry. I understand, but we’re done. I have everything I need for now. Oh, by the way, please be very careful from now on: you’re not a kid anymore and…”
The doctor hesitated, seemingly unsure whether to continue.
“You’ll have… instincts. Perfectly normal. Nothing to worry about. Even humans get them.”
Sonic froze, breath caught in his throat.
He knew exactly what she meant.
Maddie had already had that talk with him.
The one about bees and flowers, and how maturity brings certain changes, including the desire for physical contact in certain situations, maybe with “someone special.”
But how do you handle that when there are no bees and flowers, just a bee and a bigger, meaner bee?
Crap.
He didn’t want to think about it—he shouldn’t think about it.
A chill ran down his spine to his toes.
His hands were sweating inside his gloves.
“Please, not that talk… my mom already gave it to me…”
The doctor stifled a laugh as she jotted something down.
“Then I won’t add anything else. Have you noticed anything yet, by the way? Maybe toward Amy Rose or Rouge? Rouge more likely, Amy is still a bit behind you.”
Sonic almost gagged.
Rouge was basically Knuckles’ dream girl—so absolutely OFF-LIMITS.
And Sonic wasn’t into them anyway.
Girls just… weren’t his thing.
Not at all.
“No. Absolutely not!”
Too harsh. Way too harsh.
The G.U.N. doctor raised an eyebrow, clearly confused and intrigued by the blue hedgehog’s reaction.
“Oh? Because—”
“I’m not into them.”
He tried to sound firm and final, hoping it would be enough.
He really hoped she wouldn’t press further.
Please, let it go.
“Oh well, fair enough. Preferences are preferences, and they matter—even in humans, despite instincts. I imagine it’s the same for you. You’re not animals—not completely, anyway. But then again, even humans are animals. Forgive the intrusive question.”
Sonic said nothing, just gave a small nod, grateful she stopped there.
That she came to the right conclusion and dropped it.
She was young, kind—not one of the usual G.U.N. jerks.
Luckily, over the years, they had figured out it was better to keep the “aliens,” as they called them, close rather than fight them.
Smart move.
“Well, Sonic, we’re done! I’ll take off the electrodes and you’re free to go.”
GAIA, THANK YOU.
When he exited the room, he saw Rouge, Knuckles, Tails, and Amy already in the atrium a few meters away.
Usually, routine checkups were done in staggered sessions, but with the changes affecting Sonic and Shadow, they had scheduled everyone for the same day.
A bit further ahead, Maddie and Tom were talking to one of the few decent G.U.N. generals.
He smiled when he saw them and started walking their way.
But just then, to the right, someone else exited one of the medical rooms.
Sonic froze, unable to move a single step.
Oh my God.
Shadow walked out with confident, measured steps, adjusting his inhibitor rings with a scowl on his face.
His gaze focused, his mouth twisted in a slight grimace, revealing just a hint of sharp teeth.
Okay. Bad. Very bad.
His heart was pounding again.
He was going to die.
He was going to die from how illegal Shadow looked.
“Sonic…?”
A distant voice (maybe Tails?) called out to him, but it sounded like a vague background noise.
He was too focused—too focused on Shadow, who, upon hearing his name, looked up and met Sonic’s gaze in two seconds flat.
Sonic nearly lost his balance.
Those damned eyes.
“Faker.”
He said it out loud, and it snapped him out of it.
Now, dammit—focus. Be your damn self.
Please.
CALM DOWN.
“Hey, Shads!”
The smile on his face was real, sure, but barely concealed the anxiety making his vision tremble.
Everything really had changed.
Or maybe, his transformation had finally released feelings he’d been trying to suppress and hide for months.
He’d felt them—he always had—trapped between his heart and lungs for too long, but he’d never wanted to label them.
But now, ignoring them was impossible.
Admitting them was necessary.
And it terrified him—what it all meant, more than anything else.
“What are you doing here?”
Shadow’s gaze landed behind Sonic, scanning the room he had exited with distrust, barely holding back a growl.
Wait—what?!
“Did they do something to you?”
Oh!
“Hey… no…” Sonic stepped closer, placing his hands gently on Shadow’s clenched fists at his sides.
He missed a beat. Then another.
He was worried about him.
He was… oh…
“They just examined me. Same as usual. Nothing happened, I’m fine.”
Shadow looked back at Sonic and stopped growling.
His intense, probing eyes searched Sonic’s face.
He must have seen sincerity, because the fists Sonic held loosened, hands opening and, surprisingly, gripping Sonic’s.
Just a light hold—barely a few seconds.
But it sent a shiver racing through Sonic, from arms to neck.
Shadow kept looking at him—then gave a small smirk.
One of those cocky little smiles that killed Sonic every single time.
How had he not wanted to see how much he adored Shadow?
“They finally figure out your skull’s empty?”
“Ha. Ha. Ha. You’re hilarious.”
Sonic stepped back, placing fists on his hips.
“They just confirmed, once again, that I’m the fastest thing alive!”
His smile was overly confident, leaning toward Shadow with his usual swagger.
Shadow crossed his arms and rolled his eyes.
“Sure, impostor. Whatever helps you sleep at night.”
Sonic huffed—and then… an idea.
To be with Shadow.
He needed to be with him. Just the two of them.
“You know what? I’ll be waiting for you tonight—just us, one-on-one race. Between all the pain and changes these past months, we haven’t had the chance. What do you say, impostor?”
He held out his hand, like sealing a pact—as if Shadow’s word alone wasn’t enough.
An excuse to feel his warmth again, any excuse to be close, even for a moment.
Shadow looked at him, tilting his head slightly.
A slight flick of his left ear.
Then, he smirked.
Took Sonic’s hand—and with a yank, pulled him close.
They were inches apart, and Sonic felt his breath stop.
Shadow was… truly beautiful.
Majestic, devastatingly so—Sonic had envied him for that for so long.
His confidence, his calm, his strength.
Those red eyes, speckled with gold—like raw gems, mesmerizing in their depth.
And his adult form… well, it was hard to handle.
That mature body, firm muscles, more defined features, sharp teeth and claws, strong hands with thick veins Sonic could feel even through gloves.
He was perfect.
The Ultimate Lifeform.
And Sonic was lost. Gone. Done for.
His heart belonged to Shadow—every last drop of blood, every beat.
“You’ll eat my dust, little Blue.”
There it was.
The new nickname that had started since Shadow had grown taller and broader than him.
Little Blue.
Shadow had no idea what that did to his brain.
He swallowed a lump in his throat, trying desperately to keep control.
He had to.
“We’ll see, Shads. See you tonight.”
A wink, and then he walked past Shadow—without breaking eye contact.
Their shoulders barely brushed, their eyes still locked.
And then—
“Sonic?”
Shadow grabbed his wrist.
Sonic stopped, heart pounding.
“Yeah?”
“If they ever do anything to you—anything—you have to tell me. Promise me?”
Shadow’s hand tightened slightly, and his magenta eyes shone with real concern.
And Sonic, without thinking, stepped in again.
He rested his chin on Shadow’s shoulder, burying his face in the space between neck and collarbone.
His scent—lavender and coffee… intoxicating.
They’d hugged before—more than Shadow would admit (or rather, Sonic had hugged; Shadow had tolerated). And every time, his scent filled Sonic’s lungs like clean air.
“I promise.”
He whispered it against Shadow’s fur, nuzzling his nose gently into it.
Among Mobians (what little Sonic had learned from Tails), that gesture was the highest form of trust—a sacred promise.
And Shadow knew it. He’d been there during Tails’ “lesson.”
He stood still—initially tense, now completely relaxed.
He leaned in slightly, nose brushing Sonic’s ear before pulling away again.
Sonic stood upright, slipping free from the hold, creating space.
A genuine, peaceful smile.
Heart pounding.
Shadow gave a nod—then turned and walked away.
And Sonic?
He could hear his heart pounding in his ears.
“Blue really drives you crazy, huh?”
Rouge had slipped beside Shadow, sitting with him on one of the benches just outside G.U.N.
The sun was setting. He’d see him again soon.
And he felt more nervous than he had in his entire existence.
Sonic…
Who would’ve thought?
Who would’ve guessed that that unbearable hedgehog would end up, unknowingly, taking from Shadow much more than Shadow ever thought he could give?
That after countless battles, first against and then beside each other, Shadow would start feeling something so powerful for Sonic that it was almost uncontrollable?
Just Sonic’s closeness took his breath away—just like it had a few hours earlier.
Sonic’s face between his neck and shoulder… his scent of sea, fresh flowers, freedom.
Those green eyes, brighter than the Chaos Emerald itself, that smile like a lighthouse in the night.
And… damn it.
Ever since his development had ended, Shadow hadn’t been able to keep even a shred of distance from Sonic. He just couldn’t anymore.
His usual coldness, his wall of indifference, had been cracking for months—ever since he had painfully come to terms with his feelings for Sonic—and now it was full-on crumbling.
His body craved Sonic’s closeness, his warmth, his presence.
It was insane.
“Sometimes I’m almost jealous, you know? You two orbit each other like you can’t live without one another.”
Shadow turned to finally look at her.
“It’s hard to stay away from him.”
“You don’t have to.”
“He risks his life every time he’s with me. That’s not a good sign.”
“And yet you save each other. Every time. Am I wrong?”
Shadow gave a faint smile, then turned his gaze back to the slowly setting sun and the sky being dyed in hypnotic shades of orange.
He loved sunsets.
Sonic had taught him to love them.
When he told him he’d never seen one, Sonic had taken him to the most beautiful places just to show them from every possible perspective.
And those green, glowing eyes bathed in that vivid orange light… that was a sight Shadow could never get out of his mind.
“Will you tell him?”
“I can’t.”
Rouge scoffed, clearly annoyed. Crossing her arms and looking at him with a scolding glare.
“Oh, don’t start, Shadow!”
“I’m not even a Mobian, Rouge. You heard the doctors. My development only followed those cycles halfway. The other half is nothing less than a monster.”
“You think he can’t want you because of that? He’s seen you. All of you. He’s always seen you.”
Shadow’s eyes widened slightly, turning to Rouge.
That sentence meant more than Shadow was ready to understand, more than his heart was ready to bear.
And yet, he knew how true it was.
“Rouge.”
“No, sweetheart. Listen to me now. Closely.”
Rouge stood in front of him, crouching and taking his hands.
Only she—and maybe one other—could do that without getting punched in the face.
“When I look at you two… I see the strongest beings on this planet, shining like twin stars. I can’t even explain how much light you create when you’re together… and Blue, Blue lives for you.”
“How can you say that?”
“Because you don’t see.”
Shadow opened his mouth to say something, but Rouge cut him off before he could speak.
“You have no idea how he looks at you. His eyes are full of who you are. Everything you are. It’s like you’re the center of his universe and he’s a planet that can’t help but revolve around you.”
Shadow’s ears lowered, and he gently tightened his grip on Rouge’s hands, sighing.
“You have to tell him the truth, Shadow. Tell him what you feel. After this… phase you’re both going through, something’s changed so deeply between you two it’s like the air gets heavy when you’re near each other. Like this morning! Do you even realize that Tails called Sonic, and then even Tom tried, but Sonic saw and heard only you?”
Shadow could feel his heart pounding, beyond any chance of calming it.
His nerves tensed at the realization that maybe—just maybe—Sonic wanted him just as much.
“I’m not used to feelings… I don’t know how to…”
That vulnerability—one he never showed—was all there, in that small stammer, in those powerful, fragile emotions that shattered every balance.
“There’s no ‘right way’, sweetheart. Just tell him what you feel, however you can. Blue might act like a fool, but we both know he’ll understand. And even if, by some absolutely impossible chance, he doesn’t feel the same… at least it’ll be off your chest. You’d know. You’ve been stewing in this for too long, and now with everything maturing between you two, it’s only getting worse.”
Shadow said nothing, but looked at Rouge with gratitude and realization.
He knew she was right. He knew he had to do it.
Waiting would never help.
And yet, the thought of losing him—the fear of being rejected—was eating him alive.
⸻
“Are you going to tell him?”
Sonic froze, halting midway through tying his shoes.
Tails stood in the doorway, watching him with a raised eyebrow and the look of someone who knew far too much.
“What?”
Playing dumb—a trick that never worked with Tails.
“Come on, Sonic! I may only be 14, but I’m not blind, and I’m definitely not a kid!”
Sonic froze again, his heart starting to hammer in his chest. He could feel it pounding against his ribs.
“Tails…”
“No, no ‘Tails’. Are you going to tell him or not? You know, it’s starting to show. You can’t hide it anymore, not even a little. I’m surprised he hasn’t noticed.”
“He doesn’t see it because I don’t think he cares, little bro.”
Sonic stood up, a heavy weight settling in his stomach.
He was certain Shadow didn’t want him—not like that. Shadow was too far removed, too distant from that kind of feeling.
So many times, he’d seemed unreachable. So many struggles just to get closer. So much effort to get where they were now.
There was no way he could ask for more.
Not from Shadow.
That’s why he clung to what he had and did everything he could to hold onto it.
Losing him was not an option—it never would be.
“That’s what you think. Because you don’t see.”
Sonic turned away from the drawer he was rummaging through, searching for the new gloves he’d bought a few days before.
He looked at the little fox, confused.
“Seriously, you don’t see how he looks at you. I see it and I’m just a kid! It’s insane how blind you can be sometimes.”
“What are you talking about—?!”
“It’s like you’re a beam of light and he’s a moth. He can’t stay away from you.”
Sonic froze, green eyes wide, a shiver running down his spine.
“What am I supposed to say to him? ‘Hey Shadow, I’m in love with you, wanna go out?’”
“Well, that’d be a start.”
“Oh, for God’s sake!”
Sonic turned away again, slipping on his gloves with frustration.
He sighed.
He could feel the beginning of tears pricking at the corners of his eyes as fear began to clamp down on his lungs.
“I don’t want to lose him. I can’t, Tails. If he didn’t want me, if I scared him off, he’d leave. I… I don’t think I could handle that…”
There was silence—a moment that felt infinite to Sonic—then he heard Tails’ shoes on the wooden floor and felt his brother’s arms around him, tight and warm.
Air returned to his lungs; it felt like he could breathe again. The tears retreated.
He turned and returned the fox’s hug, grateful—as always—to have him.
“I’m here for you, big bro. I’m not trying to push you… Just do what feels right.”
Sonic smiled,
but the doubt began to crawl under his fur, as Tails’ words pierced into his brain like thorns.
And what if he did have, maybe, just maybe… a chance?
⸻
Their meeting came quickly.
They were running.
Running through valleys, up mountains, across gently warm sands.
They ran, and Sonic felt at peace.
Shadow at his side, matching his pace with ease, as always.
Only he could keep up with him. Only he could offer a real challenge, inflate Sonic’s ego—or deflate it like a punctured balloon.
Only him.
And no matter how far Sonic ran, Shadow would always catch up.
Just like a planet never strays from its orbit, revolving around a scorching sun that gives it life and energy enough to last forever.
That was exactly what it was between them.
Sonic did exactly that with him.
Even though it was Sonic who ran, he never really ran away. He never let Shadow go.
And yet, fear made him bite his tongue.
He buried his feelings under layers of nothing, hiding them to avoid rejection—for fear of losing him. Sonic clung tightly to whatever Shadow was willing to give.
And he ran.
Ran fast, with the ebony hedgehog at his side, looking at him with eyes full of something Sonic couldn’t quite grasp. That red so vivid and intense, it made his heart tremble and shattered every nerve.
He was so in love with him it made him nauseous.
He was so full of that feeling he could feel it in his throat, like a lump too thick to swallow.
Sometimes, it felt like he was choking on the urge to tell him.
To tell him the truth—the whole truth.
And Tails’ little speech hadn’t exactly helped his desire to stay silent.
“It’s like you’re a beam of light, and he’s a moth.”
He kept going over that one simple phrase as if it had pierced his soul and sunk its claws in too deep to pull out.
He had missed Shadow.
Missed him like air on a stifling hot day, and now all he could do was think. Think and overthink, without saying a word.
Because whatever he wanted to say would surely bring an end to what he had worked so hard to build with him.
And in that swirl of complex thoughts, he didn’t notice the obstacle in his path.
A smoothed-over rock, likely part of an old reef, hidden in the sand.
“Sonic!”
Shadow’s voice yanked him out of his mental storm—but not in time.
He tripped. Ridiculously. And fell.
But he didn’t land directly on the now cool sand, chilled by the night air.
He landed on something warm. Solid. Alive.
He felt the shape of it beneath his fingers and between his legs as they rolled through the sand together.
They ended up tangled, one on top of the other.
Sonic flat on his back against the cool sand, with Shadow above him.
His hips pressed against Sonic’s, hands planted on either side of his head.
Sonic looked up at him, trying to catch his breath as the whole situation crashed down on him like a waterfall.
He instinctively placed his hands on Shadow’s hips—and laughed.
A full, unrestrained laugh.
Maybe he was going insane.
But he couldn’t stop laughing—at his ridiculous fall, at Shadow’s scowling face, at the sheer release of all the nervous tension and embarrassment that had built up in his chest that day.
He laughed from the heart as he pulled Shadow down onto him completely,
feeling every muscle, every natural curve of the hedgehog’s body pressed against his own.
He hugged him tight.
Still laughing softly.
Finally breathing again.
Everyone knew Sonic was the fastest thing alive—but few knew that applied not only to his feet, but to his mind.
Sonic was always running. His brain never stopped. And neither did his mouth.
“I missed you so much.”
He said it with a casual ease that twisted his stomach.
He only realized what he’d said a moment later.
He buried his face into the curve of Shadow’s neck and shoulder.
Suddenly, the weight of his own words knocked the breath out of him.
And he certainly hadn’t expected the reply that came immediately after, without the slightest hesitation:
“I missed you too.”
Shadow wrapped his arms around Sonic’s back, lifting him slightly off the sand—just enough to return that intimate, incredible hug.
The blue hedgehog’s heart skipped a beat.
He pulled back a little, easing the tight grip he’d had on Shadow—long enough for it to feel like a dream.
Shadow wasn’t really the physical type—not unless it was in a fight.
And yet, he had clung to Sonic for minutes, and he was still holding on.
Sonic looked at him, studying his slightly flushed face, still breathless from their wild run and the fall that followed.
He searched those crimson eyes for the answer to a question too big to ask.
But Shadow was the one to break the silence.
“I need to talk to you about something.”
He didn’t pull away as he said it.
That could’ve been a good sign—and yet, anxiety crept up Sonic’s spine.
He kept his hands on Shadow’s hips, giving a gentle squeeze.
He could feel cold sweat through his gloves.
“O-okay…”
The uncertain stammer left his lips—his, the cocky one, the smooth-talker.
Shadow leaned in, their noses brushing, his breath warm against Sonic’s mouth.
A shiver shot down Sonic’s spine, all the way to his toes.
His heart was pounding, ramming against his ribs like it was trying to escape.
“I’m not good at this…”
Shadow’s voice was intense, low—barely a whisper in the night.
“…but I can’t keep going like this.”
He pulled back just enough to look Sonic in the eyes, locking ruby with emerald.
Panic surged through Sonic.
“I can’t keep going like this.”
What had he done? Shadow had figured it out, hadn’t he?
He knew, and he didn’t want him back—not like Sonic did. He was going to pull away, wasn’t he?
“Did I—did I mess up? I—I’m sorry, Shads—”
“I’m in love with you, Blue.”
Sonic almost lost the thread of reality.
Shadow’s words sank into him one by one, heavy as stone.
He could feel the panic melting away, replaced by an emotion so overwhelming it nearly made his legs give out.
It was hard to explain how, suddenly, the entire world stopped existing.
How everything around him lost its shape and meaning.
Even the sand beneath his back, stuck in his quills, didn’t bother him anymore.
Shadow was the only thing.
There was only Shadow.
“I know th—”
Shadow didn’t get to finish.
Because warm, soft lips crashed against his with no warning.
A kiss so hot it burned more than fire.
Peach-colored lips on his, a searing tongue tracing the edge of his mouth, asking for permission that Shadow granted without hesitation.
The fear that had nearly made Sonic nauseous just moments ago melted like snow in the sun.
He’d spent the entire run just thinking—
what to say, how to say it.
At one point that night, he’d even come up with the perfect little speech.
But he couldn’t deliver it. Not after rolling around in the sand with Sonic,
not after the way Sonic clung to him like the world might end and Shadow was the one thing worth saving.
So Shadow gave in—to instinct, to the words burning on his tongue,
to the truth Rouge had told him again and again.
He had to tell him.
He’d been dancing this emotional tango with himself for months, forgetting the steps, losing the rhythm.
So he just said what his heart screamed.
Unfiltered.
And if panic had made him instantly regret every word,
now—now, as the kiss deepened and Sonic’s hands roamed his back in frantic, blissful motion—
he couldn’t be happier he’d said it the way he did.
No big speeches. No fluff.
When they finally pulled apart, their foreheads stayed pressed together, and Shadow felt every part of his body burning hot.
“In case it wasn’t obvious…” Sonic whispered against his lips, sending a shiver down Shadow’s spine. Then another kiss.
“…I’m in love with you too. Have been for months.”
Another kiss followed that confession.
And the world stopped spinning.
Shadow picked him up effortlessly and flipped their positions.
Now Sonic was sitting on top of him.
They were both sitting, Sonic straddling him, Shadow holding his back.
The blue hedgehog hadn’t even registered the shift until he felt warmth flood his cheeks and realized how naturally his thighs gripped Shadow’s hips beneath him.
His arms wrapped around Shadow’s shoulders.
Their foreheads pressed together again.
And then, another kiss—more intense than the first.
As they held each other in an embrace so tight, there was no room for anything else but them.
“You’re really, really stuck with me now, Shads. Hope you know that.”
That cheeky grin formed on Sonic’s lips, and Shadow’s hands slid down to Sonic’s thighs, giving them a firm squeeze in warning.
His claws, just beneath the gloves, barely scratched the skin.
Sonic stifled a… sound,
eyes fluttering shut just slightly, a fierce blush blooming across his cheeks.
“Oh, little Blue… you’re the one who can’t escape now.”
Shadow dove back in for another kiss, giving Sonic no chance to reply.
And the kisses continued for what felt like forever—along with the cuddles, on that deserted beach.
With the moon watching silently, and stars burning overhead—
quiet, precious witnesses to a love that had just begun…
And was always meant to be.