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Though the sun had long since unfurled its gleaming limbs beyond the City of Mondstadt, the grass, stooped in damp obedience, clung still to the nocturne’s breath. While the ever nosy wind combed its way through the bristling tufts of Lamp Grass, stirring their pallid exhalations into the air like secrets too frail for speech. And the pond, that stagnant mirror of sky’s empty mood, held its breath in glassy silence—until a figure, dark against the morning’s apathy, bent to its edge. Kaeya’s presence in all shadow and a careful tilt, fractured the surface into spirals, as though the water itself recoiled from the knowledge of being seen.
The water did not know who stared back. But Kaeya did. Or rather, he knew the silhouette well enough to draw it from memory, if not from truth. A single bloom of Lamp Grass hung from his (fingerless) gloved fingertips, trembling from the weight of stillness.
He wore the Cavalry Captain’s coat like it belonged to someone else, though it fit him "perfectly"—navy threads sharp with gold, high collar turned up just enough to seem intentional. A long way from wine-stained cloaks and hand-me-down riding boots. Even farther from the loose, swaggering turquoise of Varka’s fashion, now subtly echoed in the confident fall of Kaeya’s shoulder cape, the way his belt buckled not once but thrice.
He bent, slowly, deliberately, to press the Lamp Grass into the water’s skin. The bloom did not float. It flailed, then sank.
“You’ll drown it that way.”
Kaeya did not look up.
He had heard the boots long before the voice. Diluc’s boots were always certain in their step, heavy in ways that Kaeya could never quite mirror, no matter how young he’d started trying.
“Then it’s in good company,” Kaeya murmured. The words were a dance, a waltz through fog.
Diluc did not bite.
He stopped a few feet away, his coat undone—mundane, mercifully so. No Vision pinned to his belt. No claymore slung to his back. Just someone familiar, red-haired and raw in the sunlight, regarding a ghost who still knew his name.
“Hmph. You always pick those.”
Kaeya looked at him then, the Lamp Grass now a bruise of blue in the mud. His eye (only one, always one) was unreadable in its glint.
“Old habits…”
“Since when?”
Kaeya offered a smile that did not reach his throat. He plucked another stalk.
Diluc watched. He always had.
When they were boys, these two from the Ragnvindr estate were inseparable.
Not twins by birth—Archons no, the stars were never so aligned—but in everything that left a trail. Bootprints in mud, breath on cold windows, two shadows cast long by the same chandelier light.
The taller one walked with certainty in motion. The other, slightly behind, stepped into that certainty as a man trying on someone else’s shoes. And they fit—mostly. Enough to pass.
They shared an appetite before they shared anything else. Bread rolls disappeared from platters in tandem. Not competition, no—Kaeya didn’t compete. He followed. He studied the way Diluc reached with his left hand though he wrote with his right, the way his fingers curled too carefully around utensils, like he was afraid of being reprimanded by no one in particular. Kaeya practiced the same nervous elegance in the mirror with a stolen spoon and ghostly patience.
Diluc climbed onto horses before he could see over their manes; Kaeya climbed, too, even when the reins slipped through his hands like snakes. He hated the lurch of saddle beneath him, hated the heavy smell of horse sweat and hay crushed into rot—but he smiled, because Diluc grinned like riding was a kind of freedom, and Kaeya didn’t want to be left behind. He smiled and bled when the reins burned his palms, smiled and fell and smiled and got back on. Every bruise was a mirror he had no name for.
Clothes? A study in forgery to Kaeya. Diluc wore starched white sleeves with prim cuffs, and Kaeya learned to fold his sleeves the same way, precisely two creases down. Diluc unbuttoned his collar one summer, flushed and defiant. The next day, Kaeya’s collar was open, too—two buttons lower. It was mimicry dressed up as evolution. Nobody looked long enough to tell the difference.
Adelinde was too busy to see it. She clucked her tongue when Kaeya and Diluc tracked mud through the halls, one set of boots small and tentative, the other sure-footed and red-stained. “They’re thick as thieves,” she’d mutter, smiling despite herself. She didn’t see how Kaeya’s movements lagged half a second behind as if he were waiting for the cue.
Crepus noticed something, perhaps. But not enough. He’d toast their shared victories over spilled juice and spilled ink, call them “fire and frost” with a voice touched by smoke and sentiment. He tousled Diluc’s hair like he was ruffling feathers. When he did it to Kaeya, Kaeya leaned in like it was a habit, like it had always been his place to belong in someone else’s warmth.
The imitation was seamless because it was never questioned.
Why would a boy copy a brother he didn’t have? Why would a child study affection like it was a language he’d missed in school?
Kaeya had his own room. Eventually. But it always felt like a stage.
He arranged his books like Diluc did, spine outward, sorted by author. He tried to hum like Adelinde did when polishing the silver. He stood with one hand in his pocket and the other gesturing in Diluc’s exact cadence—until he caught himself in the mirror, lips moving to match an echo.
Later, much later, when Diluc left the Knights, the title of Cavalry Captain was passed to Kaeya like a scarf in winter. It was warm, worn, shaped already to a man Kaeya knew too well. He wore it easily. Everyone said so.
They didn’t see the stitching.
The Kaeya who emerged after that was different. Daring, some said. Theatric. A man with a silver tongue and an eye for strategy. He knew how to dress to distract and talk to disarm. Even the Treasure Hoarders spoke of him with reluctant reverence.
But it wasn’t new. It was Varka’s laugh he mimicked now—boisterous and bold. It was Varka’s walk, open-legged and sure. Even his coat flared in the same way.
The horses had gone with the expedition, but Kaeya still practiced saddle posture in the empty stables. No one knew. They never had.
And now: Lamp Grass.
The third stalk joined the first in the water, its glow dimmed. Diluc crouched beside him, red hair catching the light like flame.
“What are you doing, Kaeya?”
Kaeya tilted his head. “Practicing.”
“For what?”
“For being someone else.”
There was a silence, but not an empty one. It was thick. Like cellar air. Like secrets kept too long in casks.
Diluc didn’t speak. He let Kaeya have the space.
Kaeya broke first. He always did.
“So… Master Diluc, do you remember the horse you named Eudyne?”
Diluc blinked. “She bit you.”
“Oh? And you told me to bite back.”
A breath of laughter, barely audible.
Kaeya glanced at the pond again. His reflection had settled, but the eyes were still wrong. Still borrowed. Still half-painted from someone else’s palette.
“I tried,” he said. “I always tried, Diluc.”
“…To bite back?”
At first, it was just a crack in the air. A soft hitch of breath that might’ve passed for amusement—if not for the way it grew. Warped. Broke into a sound not quite human.
Laughter, loud now. Sharp-edged. Something that had been caged too long and forgot how to be gentle.
Kaeya tilted his head back as if the sky itself were in on the joke. It rang out of him like a cathedral bell cracked down the middle—beautiful, dissonant, illegal. He laughed until the trees stopped rustling. Until even the frogs at the edge of the pond went silent.
Diluc didn’t speak. Didn’t flinch. He only sat there, hands stiff at his sides, as if afraid moving would make it worse.
Then—
A breath.
Kaeya folded.
Like a marionette cut from its strings, he sank into a low crouch by the water’s edge, laughter tapering into something raw. Not a sob. But the absence of one.
He dragged the heel of his palm across his jaw, then reached up—slowly, deliberately—and removed the eyepatch.
Beneath it: a shimmer. Not quite tears. Not yet.
But the eye was wet, rimmed red like something had been scrubbed too hard. The kind of redness that didn’t come from injury but from effort. From holding something in too long.
His breath fogged the surface of the pond. The reflection stared back at him, whole now. Two eyes. Both his. And somehow still not.
“To be you.”
The words spilled like wine across marble—impossible to gather once poured. Kaeya finally said it.
And then he smiled. Soft. Not mockery this time, but something else. Something hollowed out and handed over like a confession.
Diluc’s breath caught in his throat, and Kaeya finally met his gaze.
“I was never meant to exist, you know,” Kaeya said, quiet now. “I was a jackdaw in a nest of hawks. A feather in someone else’s plume.”
Not a small furrow of irritation, barely—this was deeper. A twitch at the corner of the mouth, like a muscle remembering pain. A slight narrowing of the eyes, not in anger, but calculation—as if trying to trace every moment backwards to see where he had first failed to see Kaeya not fitting. He didn’t respond right away. His jaw tensed the way it did before battles, or funerals, or birthdays that came with no one left to celebrate them.
“You were my blutsbrüder,” Diluc said at last, like one might say it to the dead.
“Heh. Was I?”
Kaeya rose.
The movement was fluid, boneless, too elegant for how tired he looked. Water clung to the leather of his boots, and the pond’s edge gave a soft, sucking noise as if reluctant to release him. The Lamp Grass shivered at his heel—violet and blue, pulsing faintly like sighs in the shade, a star trying to remember themselves.
“Every smile I’ve worn, every flourish—it’s all been stolen. Inherited. Learned. I don’t think there’s anything underneath.”
Diluc stood too. Slower. As if the gravity around Kaeya had grown heavier.
He didn’t speak right away, didn’t rush to rebut. He only looked—really looked—at the man standing in front of him like a mirror dipped in ash. His gaze moved across Kaeya’s face like fingers tracing an old scar in candlelight. Not searching for lies. Searching for pieces.
Not with suspicion.
Not with pity.
But with the bedeviled precision of someone who had once believed they understood the shape of a soul, only to find it had been a figure drawn in steam.
The ache, when it settled, was a quiet thing. Like a song only heard underwater.
And perhaps the worst part wasn’t that Diluc had missed it.
But that he’d mistaken the direction of Kaeya’s gaze for arrogance, mischief, ease—when it had only ever been longing.
The kind that never asked to be returned. Only seen.
“Well then, let’s find out what’s underneath,” replied Diluc.
Kaeya’s laugh was brittle. “And what if it’s nothing?”
“Then nothing’s finally yours.”
And the wind picked up those words and spun them gently between them. Not echoing. Just lingering. Seems like the wind itself didn’t want to decide which of them needed to hear it more.
Beneath their boots, the Lamp Grass caught the breath of the light. Pale, and stubborn.
It glowed again, casting trembling halos in the water resembling bioluminescent ghosts rising to the surface. The ripples kissed the pond’s edge. For a moment, it didn’t seem like flora. It seemed like something alive. Something listening.
Kaeya’s eyes dropped to the glow. His hand twitched—instinctive, almost startled.
Like he might reach.
Like he might kneel.
Like he might believe.
But he didn’t.
Instead, he turned. Slowly. Without a quip. Without the usual showmanship of his exit, no flick of the cape or dramatic half-bow.
Just movement.
He walked.
And behind him, the soft shuffle of another pair of boots against damp earth.
Diluc followed.
Two shadows again, not twin—but parallel.
And this time, Kaeya didn’t mimic the stride. He simply walked beside it.
For once, maybe that was enough.