Chapter Text
evolution in my veins
dream or reality (or déjà vu)?
“Someone I loved once gave me a box full of darkness. It took me years to understand that this too, was a gift.”
— Mary Oliver
It starts like this:
When Eren closes his eyes, the last thing he sees is Mikasa.
Her face is streaked with tears, her mouth trembling on words she doesn’t speak, but words he knows anyway. Her blade gleams, steady even though her hands shake. The light catches on steel, catches in her eyes, and for a heartbeat she looks like the child who once tied his scarf too tight around her neck—except now she’s the soldier about to end him.
And Eren knows this is the end.
There’s no rage, no plea left in him. Just the hollow ache of inevitability settling into his bones.
He’s alright with it. Or at least, he tells himself he is.
He only wishes—
When the world sharpens into focus, it does so with pain.
His throat burns, raw as if he’s been screaming for hours, though he can’t remember a sound leaving him. Then a knee slams into the side of his face—sharp, jarring, the crack of bone ringing louder than his thoughts.
Something shifts in his mouth. A tooth. Loose. His tongue pushes against it instinctively, and he almost chokes on the hot gush of iron flooding his throat.
The blows don’t stop. They come in constant waves, each one timed with the rise of his breath, driving the air out before he can pull more in. His chest heaves uselessly against the weight.
This feels familiar.
No.
This feels like hell.
He doesn’t look up. He doesn’t dare. He doesn’t need to see which ghost of his past has the pleasure of hurting him.
Air. He tries to drag it in, open-mouthed, desperate for something that doesn’t reek of rust and salt. But another strike hammers the crown of his head, snapping his jaw shut. His teeth shear through flesh.
The taste changes.
He sees it before he feels it—the wet slap of his own tongue hitting the ground.
It’s only then that he registers his posture. Knees ground into stone. Shoulders wrenched backward. Rope biting into his wrists until his fingers go numb. Bound.
Again.
He lifts his head, gagging on blood that spills hot down his throat and curdles cold in his stomach. His body convulses.
“Tch.”
The sound cuts through everything—sharper than the blows, sharper than the pain. His pulse spikes. That voice crawls across his skin, a familiarity so strong it twists his gut.
A boot drives into his stomach, folding him in half. This time his body doesn’t hold back; it convulses hard, forcing bile and blood up through his nose, his mouth, burning every raw surface on the way out.
“Disgusting.”
The word lands heavier than the kick. He squeezes his eyes shut, the sting of acid making them water. His hands tremble uselessly in the shackles.
And with that trembling comes the realisation.
This isn’t like déjà vu.
It is.
Slowly, he opens his eyes, lashes sticky with tears and blood. And there they are: cold, precise, unyielding. The steel-grey gaze he knows better than his own reflection.
Captain Levi Ackerman.
The world tilts, and Eren lets the blackness swallow him.
Eren dreams.
First of softness: wildflowers bending in the wind, sunlight pooled in endless stretches of water, laughter carried like birdsong. Gentle grey eyes, steady hands. Nights that run too long, burning bright with joy, blurred by wine and careless touches.
Then of endings: walls collapsing, titans screaming, fire spreading faster than thought. Faces split open by grief. Blades flashing. Explosions that don’t stop even when you close your eyes.
He dreams forward, and backward, and all at once. The weave of lives he’s lived tangling in his chest until he can’t breathe.
Maybe this is the truth of his punishment.
Maybe he’s bound to walk the Paths forever, cursed like Ymir to dream of everything—past, future, and the unbearable present—and never know which one is real.
Maybe death is just reliving the worst parts of your life over and over and over.
When Eren wakes, the first thing on his tongue is bitterness.
Failure.
It coats his lips like ash, crawls down into his chest until it sticks heavy to his ribs. His body feels weightless and leaden all at once. The couch beneath him is unfamiliar, too soft to be the aftermath of death, too real to be a dream.
He died. He remembers it—Mikasa’s face carved with grief, her blades flashing, the instant before everything went black. She killed him because he left her no choice. Because he’d become the very monster he swore to fight.
He needed to be the enemy to make them all heroes. To save them.
So why is he breathing now?
Did he only imagine meeting the Captain again? A memory playing on loop? But if that’s true, why does he seem to remember it twice—two sets of images layered over one another, both vivid, both true?
“He’s awake.”
The words snap through him like a whip. He bolts upright too fast. His stomach revolts. He folds over, gagging into the bucket that someone had thought to place beside him.
“Geez, Levi, did you have to hit him so hard?”
The voices hit harder than the nausea. Familiar. Too familiar. It’s been years since he heard them all alive in the same room. Years—or minutes? His throat closes, a sob strangling itself before it can escape. His chest aches with the weight of knowing he’s back at the start.
Back when there was still a chance.
Back when he could still pretend hope wasn’t a lie.
“It’s just a dream,” he whispers into the rim of the bucket. His stomach convulses again, but nothing comes out except bile, sharp as liquor, burning a trail up the back of his throat. The taste drags him somewhere else—tents filled with laughter, nights blurred with warmth and wine, cheeks aching from smiling too long. And then, the dark. The silence. The ruin he left in his wake.
He blinks hard. His vision clears just enough to notice the absence: his hair doesn’t fall into his face anymore. Too short to grab, to hold back. He hasn’t had hair this short in since he was fifteen.
A dream. It has to be.
“Did you say something, honey?”
“He’s in shock, I think.”
“What the hell did you do to him, Levi?”
“Tch.”
The voices blur together, sliding over one another until they’re indistinguishable. He clutches at fragments but they slip through his fingers. It’s all too muddled, too unreal. His mind claws for something solid—the Attack Titan’s memories, the threads of past or future, anything that tells him where he is.
Nothing.
Just emptiness.
Maybe it’s the past. Maybe the future. Or maybe this really is hell. It would fit.
He digs deeper. Deeper. Searching for scraps, echoes, warnings—
He finds nothing.
Strange.
He runs his tongue over his teeth—whole. Smooth. So he still has Titan powers, then. He’s certain he saw the bloody thing roll across the floor only minutes ago. Or was it hours? Days? Time feels elastic, stretching and snapping back with every breath.
“I—” The sound tears from him like glass down a chalkboard. His throat revolts, forcing him to dry-heave over the bucket again.
A cool rim presses against his lips. Water. He drinks greedily, swallowing too fast, spilling some down his chin. The chill soothes his throat, the ache in his chest easing for a moment.
“Better?”
Eren finally drags his gaze upward—and freezes.
Two figures stand before him. The thirteenth and fourteenth Commanders of the Survey Corps. The sheer size of Erwin Smith knocks the air out of him. Walls, had he always been that tall? His memory flickers—the man crumpled in the dirt, one arm gone, blood soaking his coat.
Is? Was?
“Yeah,” Eren whispers. His voice is thin, barely more than breath.
Squad-leader Hange crouches, her eyes already darting across his bruises, cataloguing each one. She presses another cloth into his hand and offers a gentler smile than he remembers she was ever capable of later on.
“Does it hurt?” She asks, dabbing carefully at the swelling along his cheek.
Eren opens his mouth to answer—but Commander Erwin’s voice rumbles over hers.
“I am sorry about that.”
That voice. unyielding, commanding, impossible to ignore. It vibrates through Eren’s chest, dragging old loyalty out of places he thought long hollowed.
His face is kind as he looks between Eren and the corner of the room. When Eren follows the line of Commander Erwin’s gaze, he sees him.
Captain Levi.
Leaning against the wall, arms folded. The picture of indifference. But his eyes—grey, and sharp and just as Eren remembers—flicker with something Eren recognises too well.
Regret.
It drops into Eren’s stomach like a stone in deep water. Heavy. Wrong. He shouldn’t know Captain Levi that well. Shouldn’t be able to read the faintest shadows in his eyes. He doesn’t deserve to.
“But we needed to do what was necessary to have you turned over to us,” Commander Erwin continues, calm as a man explaining the weather.
“Yes, sir,” Eren replies without hesitation. “I understand.”
The Commander kneels, irrationally tall even from that angle, and extends his hand. “You have my respect,” he says.
Eren’s breath stutters. The words hit differently this time—familiar yet altered, like echoes shifting in a tunnel. He clasps the outstretched hand, fingers gripping harder than he means to, memorising every line in the Commander’s face as if it might change the moment he blinks.
The Commander’s grip is firm, immovable—nothing like the chaos pounding in Eren’s ribs.
Movement draws his attention. Captain Levi has moved from the corner of the room and now lowers himself onto the couch, the faint rustle of his cravat crisp against the hush. His arm drapes along the backrest, not quite touching, but the warmth bleeding from him is close enough to set the fine hairs at Eren’s nape on edge.
Heat ghosts the space between them. Eren shivers.
Last time, he’d flinched—a green recruit startled by proximity to the Captain. Now, with years of blood and rubble in his bones, the knowledge of what it feels like to have the weight of the world on his shoulders, the reaction is quieter… heavier. He turns his head, letting his gaze trace familiar lines: the sharp cut of cheekbone, the controlled set of the Captain’s mouth. The white cravat, unrumpled as if time itself wouldn’t dare disturb it.
He’s exactly as Eren remembers him. Untouched. Unscarred. And for a fleeting moment, the restless churn in Eren’s chest eases, calms—as if this one thing, at least, is safe from change.
And something deep inside Eren loosens. A knot he didn’t realise was strangling him finally gives way.
“Say, Eren—” Captain Levi begins.
“No.” The word leaves Eren before he can stop it. His throat burns, but he pushes on. “I don’t resent you. You did what you had to. I understand.”
The Captain’s eyes flicker—surprise, quickly shuttered. His mouth smooths into the familiar mask of apathy, but Eren can see it now, the spark of intrigue smouldering beneath.
“You did take it a little far, though, Levi,” Squad-leader Hange cuts in with a grimace. She thrusts out her hand. “You lost a tooth, Eren.”
The Captain’s reply is dry, almost dismissive. “He also bit through his tongue. But you don’t hear him whining about it.”
“It grew back,” Eren murmurs, too soft, too careless. The truth slips out before he can stop it.
The Squad-leader’s eyes widen, and he braces. Three, two, one—
“I know! Fascinating! I can’t believe it regenerated so fast!”
Eren cringes at the volume, shoulders hunching instinctively. She mistakes it for fear, her enthusiasm softening as she waves her hands.
“Don’t worry! I won’t dissect you!”
“That’s…” Eren swallows, trying to find a word that doesn’t taste bitter. “Comforting,” he settles on.
Squad-leader Hange beams, her grin stretching wide, open, unscarred by loss. Eren can’t look away. It’s been so long since he’s seen her smile without grief lurking behind it.
He stares, and keeps staring, because he knows it won’t last.
Eren already knows where they’re headed before anyone says a word. He’d lived there once—years, in another life. Knew every drafty corridor, every creaking floorboard, every nook where he could vanish when the Captain went on one of his cleaning frenzies.
The memory drags a snort out of him. Strange, how those moments linger untouched, even when newer memories pile in like stones on top of them. It feels less like remembering and more like housing two people inside the same body: the boy he once was, and the man he’s been forced to become.
Once, he was Humanity’s Hope. Now, he carries the burden of being it twice.
If this isn’t hell, it must be the cruellest nightmare Ymir could conjure.
The weight of that title presses down until his ribs ache. He shoves it aside and fixes his eyes on the road ahead instead. The castle. For a moment, he lets himself think of all the good memories bound up in its stones—nights spent with laughter echoing through the halls, warmth before everything cracked open.
The Captain glances back at him, one eyebrow arched in quiet scrutiny. He says nothing, but the look is enough to make Eren’s pulse stumble.
“… But being so far from rivers and the Walls, this castle ended up being practically useless for the Survey Corps,” Oluo drones on, voice calm yet laced with that irritating arrogance. Eren barely catches the words. He’s too busy being struck by the fact that he’s missed them—all of them, even this ridiculous man with his smug tone and copied mannerisms.
By the Walls, though, he has not missed how much Oluo imitates the Captain.
Still, he lets the chatter wash over him. He knows this speech already. Soon enough Oluo will puff himself up, call him a greenie, maybe try to remind him of his place—
“Don’t get cocky,” Oluo snaps, right on cue. “I don’t care if you’re a Titan or not. Walls, I can’t believe Captain Levi is going to be spending all his time with you. Did you know—”
The sentence cuts off with a yelp. Blood dribbles from Oluo’s split tongue as he fishes out a cloth and dabs furiously at the mess, muttering to himself.
Eren can’t help it—he snickers. Past and present overlay, memories of Oluo’s endless posturing colliding with the identical scene playing out now.
The Captain glances back again. His eyes flick between Oluo’s silent grimace and Eren’s poorly stifled laughter.
And before he can think better of it, Eren meets the Captain’s gaze and winks.
His chest tightens instantly. What the hell is he doing? His fifteen-year-old self would never have dared. But this isn’t the same Eren. Not anymore.
Perhaps it’s the dream—if that’s what this is. Perhaps it doesn’t matter if he lets slip how obvious his admiration is. It’s not as if anything real could come of it.
Unless this isn’t a dream. Unless it’s death. Maybe he’s trapped in the moment between breath and oblivion, head already severed from his shoulders, replaying his entire life in one stretched-out heartbeat. For him, it’ll feel like years. For Mikasa, for the Captain, for anyone watching his body fall—it’ll be no longer than a second.
So whether this is a dream, a death-hallucination, or some twisted hell, the truth remains.
His foolish flirtation with the Captain—even sharper, bolder this time around—will never amount to anything.
Right?
It’s just a dream.
Eren repeats the words over and over, like a prayer, as the Captain assigns them tasks to clean the crumbling castle. He repeats them again when Petra slips close, voice hushed and eager, telling him about the Captain’s underground life as though it’s a story worth treasuring. And he keeps repeating them, like a tether, through the long, dragging hours until dinner.
“We’ll be on stand-by until the end of the month,” Eld says at last, cradling his tea between scarred hands.
Eren already knows why. He knows the timetable as if it’s carved into him. But still, he asks, “Why?”
“We’ll have a large-scale expedition beyond the Walls by then. And we’ll be bringing this year’s recruits with us.”
The words stop him cold. His chest seizes, lungs refusing to pull in air. Because now he remembers exactly when this dream began.
Marco.
No matter what he does, he won’t be able to save Marco. Not from Reiner. Not from Bertholdt. Not from Annie.
The thought is ice trickling down his spine, sharp and merciless. He sees their faces in flashes—comrades he’d once called siblings, all of them smiling with secrets behind their teeth. Months he’ll spend beside them, laughing, training, living in the shadow of a betrayal he already knows is coming.
How the hell is he supposed to act normal?
“Do we have to?” He asks, his voice too tight, too deliberate. Already, he’s noticed small cracks, hints that this dream isn’t a perfect reflection of what he remembers. And if it is his dream, he should be able to bend it, steer it away from the endings he dreads.
Right?
“Don’t you want to see your friends?” Petra tilts her head, offering him a smile that feels too gentle, too young. She’s only three years older than him now—eighteen. But she carries herself with the weight of someone older, someone steadier.
Watching all your friends die will do that, his mind supplies bitterly. He knows it’s true. He’s lived it.
“It’s not that, I just…” He falters. Words scatter. There’s no way to answer without tearing open questions he can’t afford.
“He doesn’t want his friends to join the Corps,” the Captain cuts in smoothly, “and he certainly doesn’t want them outside the Walls.”
Eren startles slightly at the accuracy. He doesn’t know if the Captain is reading him or simply stating the obvious, but either way—it lands.
“It just feels sudden,” he murmurs. “Trost took a toll on them.”
The Captain’s eyes flick towards him, unchanging and unreadable. Eren thinks about that last bit. Unreadable.
Earlier, he’d been able to clearly see the regret in the Captain’s eyes, but now he can’t even guess whether he likes his dinner or not. Maybe Captain Levi wanted him to see the regret he felt. But then, why was that so important for him?
“It’s not my job to make plans. But knowing the Commander, he has more than one trick up his sleeve.” His tone is final, shutting the subject down as neatly as closing a door.
The way the Captain shuts down conversation, efficient and absolute, reminds him of Mikasa. Family resemblance, maybe.
But Captain Levi’s words echo oddly in Eren’s head—almost identical to the conversation he remembers, but shifted, as though the dream is rewriting itself while he listens. He knows, any moment now, Squad-leader Hange will come through the door with that too-bright grin.
“At least we have a new hope now,” Eld says, voice low but certain.
Eren stiffens. Of course. Even here—even in his own head—he can’t escape the label. Humanity’s Hope. The weight that crushed him once is settling on his shoulders again, heavy as ever.
Why would he conjure this? Why would his own mind force him to live the failure again and again and again?
He wants to say it out loud—this is a nightmare. But he knows the truth. The place he left behind was the nightmare.
This?
This is something else. Not better. Not kinder. Just… different.
For now.
It’s just a dream.