Archive of Our Own

I.

It begins, as all terrible ideas do, with a hypothesis. Albedo, famed Chief Alchemist of the Knights of Favonius, honorary consultant to several international academies, and absolute menace to peace and quiet in Mondstadt, has decided—

—that Kaeya Alberich is unreasonably powerful.

Not magically. Not militarily. Not tactically. No, no. That, Albedo could accept. Expected, even. In fact, he admires it. Kaeya’s swordplay is admirable. His vision, versatile. His strategy, typically foolproof.

The problem is the other thing.

The problem is that Kaeya Alberich is too charming, and everyone falls for it, and Albedo is not immune.

Which is unacceptable.

Which is unscientific.

Which must be… replicated.

He has, of course, drafted a list. The list is currently twelve pages long, pinned with butterfly clips, categorized under CHARM VARIABLES OBSERVED in triplicate.

Kaeya, he has noted, tilts his head precisely four degrees when speaking to the elderly. Albedo has measured. There is a subcategory on the “grandmother tilt,” complete with illustrations. Kaeya, also, flashes his eye—just one, the visible one—precisely when he is lying. He’ll say, “Of course, Acting Grand Master, I definitely did not climb the cathedral spire to retrieve the missing wine barrel,” and then he’ll wink, and the entirety of the Knights will sigh as if they’ve been swooned into temporary amnesia.

Even Jean.

Albedo has run the numbers. It’s a pandemic.

Kaeya’s smile causes statistically significant drops in public resistance. His laugh—low, lilting, often with that infuriating rasp of amusement—has a paralytic effect. Mostly on barmaids, diplomats, and, disturbingly, Lisa.

More distressing still: the documented Kaeya Touch Effect—a brief, grazing contact on the arm, wrist, or lower back, accompanied by some irreverent nickname like “darling” or “comrade”—has been known to make even hardened Fatui agents reconsider their allegiance. The Grand Master himself once said, after a diplomatic banquet gone catastrophically well, “Kaeya could end a war with a well-timed smirk.”

Albedo believes it.

He’s seen it.

He’s been ruined by it.

This is not ideal.

This, Albedo concludes, must be rebalanced.

Which is why, one fine spring morning in Mondstadt, Albedo stands outside the cathedral with a clipboard, an overcomplicated plan, and a goal.

“I will flirt,” he informs Sucrose.

Sucrose, who was simply passing through with a small crate of hybrid anemones, stops walking. She stares at him like he’s replaced his blood with nitric acid.

“You’ll what?”

“I will flirt,” he repeats. “With Kaeya. For science.”

Sucrose makes a sound that might be a hiccup. It might also be a pre-sneeze. Or, possibly, the death of language itself.

Phase One of the plan is titled: Seductive Nonchalance.

It goes poorly.

Albedo tries leaning on the cathedral gate. He means to look casual. Aloof. Romantic. Windswept.

He falls.

Sucrose tries to help him up but ends up tripping on the flowers.

A nun faints.

Kaeya arrives five minutes late, entirely unaware that Albedo has been rehearsing a flirtatious eyebrow raise for approximately forty-seven minutes. Kaeya arrives with a coffee in hand, sunglasses perched on his forehead like a bastard, and that too-tight tunic that he knows makes him look like Mondstadt’s collective problem.

“Albedo,” Kaeya says, smiling like the dawn is something he invented. “Are you... loitering?”

“Engaging in observational behavior,” Albedo says, dusting off his coat.

Kaeya quirks an eyebrow. “Of the nuns?”

“No. Of... wind currents.” Pause. “And... facial angles.”

Kaeya takes a sip of coffee. “Is this about the incident with the diplomat and the pomegranate liqueur again? Because I swear, that wink was—”

Albedo interrupts. “Flirting,” he announces. “I am attempting it.”

Kaeya chokes on his coffee.

Sucrose will later describe the next three minutes as “watching two very powerful people both lose brain cells in real time.”

Kaeya stares. Albedo stares back. Kaeya looks, astonishingly, like he might faint now.

Then, Albedo—bless him—steps forward. Leans in. Places a hand on Kaeya’s arm. He even tilts his head, four degrees. He has practiced this.

“You have very symmetrical facial features,” Albedo says.

Kaeya blinks.

Albedo nods solemnly. “I would like to touch them.”

The silence is so profound, pigeons re-evaluate their life choices mid-flight.

“You…” Kaeya starts, voice low. “You want to touch my... face?”

“For data,” Albedo says gravely.

Sucrose dies quietly in the corner.

Kaeya is trying very hard not to laugh.

“Oh? And what sort of data are we talking about?”

Albedo lifts his clipboard. “Muscle reaction to proximity stimuli. Eye dilation. Dermatological heat signatures. Also, a sample of your vocal pitch when flustered.”

Kaeya’s mouth opens. Then closes.

Then, with great dignity and a barely contained wheeze, he says, “Albedo. Are you trying to seduce me?”

“I am attempting to replicate your behavior to better understand its impact on inter-organizational diplomacy,” Albedo replies. “Also, yes.”

Later, Kaeya will recount this to Diluc over drinks and nearly fall off the barstool from laughter. Diluc will, in response, threaten to revoke his tavern citizenship.

Later still, Albedo will carefully edit his field notes to read: “Attempt #1: Flirtation, Failed. Subject exhibited signs of confusion, amusement, possible cardiac irregularity. However: did not recoil. Encouraging.”

Still later, after much chaos, two ruined clipboards, one near-international incident (don’t ask), and several more attempts at “charm,” Kaeya will look at him across a candlelit table and murmur,

“You know, you didn’t have to experiment, Albedo. You had me the moment you tried to tilt your head and fell over.”

Albedo will blink. “Really?”

Kaeya will grin. “You’re terrible at flirting. It’s adorable.”

And Albedo—who has since begun cataloguing Kaeya’s Reaction to Compliments at Various Levels of Intimacy—will hum thoughtfully and say,

“Then I’ll continue until I’ll get better.”

And he does.

II.

It begins, like most scientific disasters and romantic entanglements do in Mondstadt, with alcohol and ambition. Which is to say: Springvale's Annual Moonrise Banquet.

It is the kind of event Kaeya usually avoids until the last possible minute, then attends with great fanfare and greater cleavage. He’s already worn the blouse—you know the one, the one that makes bards lose their rhymes and waiters forget their trays—and he’s already kissed three diplomats on the hand, just to prove a point.

It is, in short, a normal night for Kaeya.

Until Albedo arrives.

Until Albedo arrives wearing black. With a collar sharp enough to kill a man. With two fountain pens tucked behind his ear like weapons. With that goddamn quiet menace in his eyes like he’s studying everyone in the room and judging their proportions.

And Kaeya—Kaeya, who once navigated a snowstorm with a blindfold and half a bottle of apple schnapps—almost drops his wine glass.

“Evening,” Albedo says.

Kaeya swallows.

“Evening,” he replies, coolly. Smoothly. Unbotheredly. As if his brain is not currently screaming like a goat caught in the cathedral bell tower. “You look... ready to assassinate someone. It’s breathtaking.”

Albedo nods solemnly. “I’ve prepared a joke.”

Kaeya blinks. “You—what?”

“A joke,” Albedo repeats. “Like you do. To charm people.”

Kaeya opens his mouth.

Kaeya closes his mouth.

Kaeya sets his wine glass down very carefully and tries not to think about the last time Albedo “prepared” something. (The floor did eventually grow back. Mostly.)

Albedo takes this as encouragement. He pulls a small notecard out of his pocket. “I workshopped it with Timaeus.”

Kaeya wants to die. “Of course you did.”

The banquet is loud, swirling with diplomats, merchants, high-profile scholars, and at least one bard attempting to seduce the wine. The wine is indifferent.

Kaeya and Albedo stand near a balcony, watching the chaos with the kind of shared silence that only comes from people who have each, separately, committed morally ambiguous crimes for love and/or science.

Kaeya sips his wine again.

Albedo holds up the card.

“Why,” Albedo says with grave solemnity, “did the alchemist refuse to date the cryo user?”

Kaeya inhales wrong. Coughs. Coughs harder. “Albedo—”

Albedo continues, entirely undeterred. “Because he said: ‘You’re too cool to handle. I might sublimate.’”

There is a silence. It is the kind of silence usually reserved for funerals and diplomatic incidents.

Kaeya wheezes.

Albedo looks at him expectantly. “Well?”

Kaeya puts a hand on the balcony railing to steady himself. “That was—Albedo, that was unbelievably terrible.”

Albedo blinks. “You smiled.”

“I’m smiling because I’m trying not to scream.”

Albedo studies him. “Fascinating.”

And that, Kaeya realizes too late, is the smile study face. That’s the face Albedo makes when he’s about to destroy public infrastructure in pursuit of a romantic revelation.

Fifteen minutes later, Albedo is telling the same joke to a visiting Snezhnayan trade envoy.

Ten minutes after that, the envoy is so charmed by Albedo’s delivery (which is dry, sharp, and somehow laced with understated menace) that he agrees to lower tariffs on Mondstadtian imports.

By morning, Jean is calling it a “victory for Mondstadt’s scientific diplomacy.”

Albedo calls it “an experiment in interpersonal affect.”

Kaeya calls it “a war crime.”

Later, in his laboratory, Albedo logs the results:

“Attempt #2: Humorous Quip. Results: Surprisingly effective. Kaeya turned red. Diplomat surrendered. Overall, a successful replication of subject’s charm protocols.”

Kaeya, reading over his shoulder, snorts. “You say ‘surrendered’ like we annexed Snezhnaya.”

Albedo shrugs. “We could.”

Kaeya leans in. “Are you flirting with me again?”

“Yes,” Albedo says.

Kaeya does not kiss him.

Not yet.

Not because he doesn’t want to. No.

He absolutely wants to.

It’s just that he’s afraid if he kisses Albedo right now, the alchemist will draft a ten-page paper titled On the Lip-Tilt Angle of Kisses Received Mid-Experimentation.

Kaeya’s not sure he has the emotional fortitude to be peer-reviewed in bed.

Still, that night, when he stumbles back to his room—tipsy, wrecked, ridiculous—he thinks about that joke. He thinks about Albedo, quiet and terrifying and beautiful, trying to tell a pun like it’s an assassination. And he thinks about how the laugh caught in his throat like it wanted to stay there forever.

The next morning, he finds a note slipped under his office door.

“I’ve prepared a second joke. Will test results on you tonight. Dress provocatively.”

Kaeya sits down.

Kaeya puts his face in his hands.

Kaeya laughs so hard he nearly falls out of his chair.

III.

The third attempt begins with a scarf. Not Kaeya’s vision-bearing, low-slung, shoulder-draped signature scarf—though that one is its own diplomatic incident waiting to happen (Albedo has measured it for “fabric weight against clavicle tension during humid weather flirtation maneuvers,” and Kaeya had to sit still for a full seventeen minutes while trying not to die)—no, this is a different scarf.

This is a new scarf. A custom scarf. A hand-knitted, scientifically calibrated, tragically overengineered scarf.

Made by Albedo.

For Kaeya.

As part of a new experiment in Tactile Allure and Gift-Based Affection Transfer.

---

The notes are concerning.

Albedo has diagrammed several contact zones: hand-to-hand = low risk, high potential intimacy; forearm = neutral; shoulder = high risk, may initiate Kaeya-specific giggle reflex. There is a subcategory labeled “accidental brush vs. intentional offering.” Another lists case studies: “Kaeya offering a cloak to Lisa in winter, result: mild flirtation. Kaeya adjusting Diluc’s collar once at a ball, result: continent-wide rumors.”

Albedo has concluded that Kaeya’s charm is not just verbal. It’s also material. Tactile. His gifts are rare, but when offered—absurdly thoughtful. Like the time he handed Albedo a jar of imported cherry compote because “it reminded me of that one expedition where you almost died of boredom.” Like the time Kaeya found a pressed Starconch between the pages of Albedo’s sketchbook. Unlabeled. Unexplained.

Albedo had stared at it for twenty-seven minutes, then flushed. Which was deeply inconvenient, because he had not scheduled emotional response testing that day.

So: a gift. A gesture. An equal and opposite reaction.

A scarf.

---

It is teal and deep navy, soft as Kaeya’s voice when he’s being dangerous, stitched with tiny silver flecks that glitter in the sun like snow on a windborne shoulder. Albedo chose the fiber based on Kaeya’s temperature tolerances—measured by “incidental” shoulder touches during sparring—and double-checked for wind resistance across high altitudes (Kaeya’s ponytail suffers so). The scarf is absurd. It is perfect. It is the softest thing Albedo has ever made.

He brings it to the Favonius library, where Kaeya is pretending to read a report and actually scribbling “K.A. was here” on the back of a diplomatic map.

Albedo enters with the grace of a man attempting normalcy and achieving instead exactly the opposite. He hovers for too long.

Kaeya glances up, still scribbling. “What has three eyes, thirteen pens, and keeps inhaling behind me like a haunted lungfish?”

Albedo swallows. “I made you something.”

Kaeya pauses.

Kaeya turns.

Kaeya sees the scarf and—Gods, it's subtle, but Albedo catches it—his expression shifts like a current beneath the sea: something flickers, something softens, something stops.

“For me?” Kaeya says, like it’s a joke and a dream and a trap all at once.

“I factored in your height, average breeze exposure, and likely excuses to wear something dramatic,” Albedo replies. “Yes.”

Kaeya takes it. Holds it. Looks at it like it’s a creature he hasn’t seen before and isn’t sure if it will bite or weep. Then he loops it—reverently—around his neck.

It fits.

Of course it fits.

Albedo measured it against his own collarbones in the mirror and imagined what it would look like brushing Kaeya’s throat.

Kaeya fingers the edge. “How do I look?”

“Compelling,” Albedo says, and his voice does not waver, but it does deepen, and Kaeya looks up at him with something dangerous and fond flickering in that single glinting eye.

Albedo’s hand twitches. Almost rises. Almost brushes the line of scarf over Kaeya’s pulse. Instead, he coughs.

“Hypothesis,” he says, because he is an idiot: “Physical gifts may create opportunity for increased proximity without triggering defensive flirtation reflexes.”

Kaeya just stares at him. Long. Quiet. He leans back in his chair. Stretches. The scarf slips, just slightly, baring one shoulder.

Albedo forgets how breath works.

“Oh, you can come closer than that,” Kaeya says. He says it low, amused, voice like sunlight filtered through wine. “I don’t bite.”

“That is factually incorrect,” Albedo says, and then wants to die.

Kaeya bursts out laughing. Not just a chuckle—a full laugh, rich and wrecked, like he’s delighted and stunned and stupidly, stupidly fond. He leans forward again, elbows on the table, scarf pooled like a secret around his neck, and looks up at Albedo.

“You’re learning,” he says. “Dangerous.”

Albedo shifts, unsteady, very aware of how close he is now, and how Kaeya is still leaning forward, and how his hair smells like pine smoke and rosewater, and how—

“You’re not just experimenting,” Kaeya says, quieter. “Are you.”

Albedo goes still. He doesn’t respond.

Kaeya tilts his head. Not four degrees or grandmother tilt. The Albedo tilt, he thinks. The one Kaeya only does when he’s studying Albedo.

Albedo is not prepared for this.

Kaeya raises a hand. Just slightly. Almost brushes it against Albedo’s sleeve. Almost.

But not quite.

He lets it fall.

“I’ll wear it,” he says, voice suddenly light again, breezy, a step backward that makes Albedo ache. “Everywhere. See if it gets me more free wine at Angel’s Share.”

“You’re... welcome,” Albedo says. It sounds wrong in his mouth. His mouth is dry. His everything is dry. He is going to combust.

And then Kaeya stands. Walks off. Tosses a smile over his shoulder like a shot across the bow.

The scarf glints.

Albedo’s brain blue-screens for seventeen minutes.

---

Later that week, ten citizens of Mondstadt see Kaeya wearing the scarf and ask him if he’s courting someone.

Two priests take it as a sign of divine favor.

A poet in Liyue writes an ode called “The Blue and the Beautiful” that sells seven thousand copies and causes a spike in scarf sales.

Kaeya reads it aloud at a tavern.

Albedo listens from the shadows.

He almost kisses him.

Almost.

But Kaeya catches his eye across the bar, and winks, and Albedo forgets how to walk, so the moment passes.

He goes home.

He writes, Attempt #3: Tactile proximity via hand-crafted object. Results: inconclusive. Subject extremely beautiful. Nearly lost higher function. Further testing required.

And at the very bottom, he writes:

“Also: Kaeya looks good in navy.”

He draws a heart.

He denies it later.

IV.

By the fourth attempt, the Knights of Favonius have started taking bets. Not on if Albedo is attempting to flirt with Kaeya again (that part is already legend, passed from squire to cook to archivist with the reverence of folklore) but on how. How will he do it next? With charts? With deadpan innuendo? Will the city survive?

The current favorite is “accidental poetry reading at swordpoint,” which, frankly, says more about their expectations than reality.

Reality, as always, is worse.

Because this time, Albedo has chosen… compliments.

He has observed, with the careful horror of a man studying a venomous flower, that Kaeya compliments people as easily as breathing. “Love the boots,” to a diplomat. “Sharp new blade,” to a trainee. “Your hair is practically singing today,” to Lisa, who had laughed for four minutes and then touched his arm. Albedo had not recovered.

Kaeya’s compliments work not because they are accurate (though they are), but because they are delivered like a conspiracy—like a secret between the lips of a sinner and the heart of someone who wants to be ruined.

Albedo has tried to resist them. He has failed.

So now, in a wild act of tactical escalation, he will reverse the equation.

He will compliment Kaeya. Just once.

To test its effect.

To observe the power shift.

To see, perhaps, if Kaeya’s smile can be turned inward. Bent. Redirected. Melted under his heat.

This, of course, goes about as well as one would expect when the experimenter is a disaster in human form and the subject is a peacock made of silk and suffering.

---

The setting is Windrise. The lighting is dramatic. Kaeya, of course, arrives looking like he was carved from dusk—dark blue coat thrown open like sin, shirt half-unbuttoned, boots polished, eye glittering like moonlight caught in a glass of brandy. He does not walk. He glides. A breeze follows him like a dog.

Albedo is already seated beneath the Tree, sketchbook closed for once. He stands when Kaeya approaches and—for once—does not immediately launch into a discussion of rune geometry, blood density, or experimental wormhole theory.

This is the first sign something is wrong.

Kaeya watches him warily. “Albedo.”

“Kaeya.”

Silence.

“Did we have a meeting scheduled?” Kaeya asks, ever the prince of pretty evasions. “A surprise picnic? Am I about to be dissected again?”

“No,” Albedo says.

“Ah,” Kaeya says, smiling like the blade of a knife being polished. “So you’ve lured me here to murder me.”

Albedo blinks. “Would you prefer that?”

Kaeya stares. “No.”

Albedo nods. “Then I will begin.”

Kaeya opens his mouth. Closes it. He has been in battlefields. He has faced abyssal horrors. He has never been so afraid in his life.

“I’ve been thinking,” Albedo says slowly, like the words are being measured for weight. “About the structure of admiration.”

Kaeya’s mouth twitches. “As one does.”

“I admire you,” Albedo says.

Kaeya freezes.

The wind stops. The entire continent tilts sideways.

“You—what.”

Albedo nods, solemn. “You are deeply efficient. You adapt quickly to new roles. You exhibit an unusually high resistance to interpersonal stressors, and your response to threats is both creative and effective. Also, your laugh causes minor arrhythmia.”

Kaeya stares at him like he’s grown a second head and it’s reciting poetry.

“I—thank you?” he tries.

“That was not a compliment,” Albedo says, checking his notes. “It was a statement. The compliment is next.”

Kaeya whispers, “Dear Barbatos.”

Albedo takes a breath. Steps forward.

Kaeya does not move.

“You,” Albedo says, “are so catastrophically attractive that I have, on multiple occasions, dropped glassware in your presence.”

Kaeya forgets what gravity is.

“You walk like a problem I want to study,” Albedo continues, voice low and strange and sure. “You speak like a secret. Your hands are steady enough to wield a sword, a pen, a body, or a heart. And I—”

Kaeya makes a sound. Something between a gasp and a laugh and a whimper.

Albedo falters.

For the first time, he looks… uncertain.

“I… apologize,” he says. “Was that incorrect? Did I miscalculate?”

“You—” Kaeya’s voice breaks. “You—you just said—you—”

Albedo waits.

Kaeya breathes. Laughs once. Then throws his hands into the air and shouts at the sky, “WHAT IS HAPPENING?!”

A nearby bard drops their lute.

Fifteen minutes later, Kaeya is pacing. The scarf Albedo made him is hanging off one shoulder, half-choked with panic, half-flushed from the sheer audacity of being complimented like a person instead of a paradox.

“You—you can’t just—say those things,” Kaeya says, still walking in circles. “You can’t say my laugh causes arrhythmia. You can’t describe my walk like a mathematical flaw. You can’t—can’t want to study me. People don’t say those things.”

Albedo is watching him. Calm. Cool. A little curious. A little hurt.

“You say them,” Albedo says. “To others. Frequently.”

“That’s different.”

“Why?”

“Because I’m me!”

Albedo tilts his head. “And I am me. Why is it different when I—”

Kaeya lunges forward and grabs his shoulders.

Albedo blinks.

Kaeya’s hands are trembling.

“You cannot look at me like that,” Kaeya hisses.

Albedo does not flinch. “Like what?”

Kaeya’s voice drops, almost cracks. “Like I’m worthy.”

Albedo goes still.

The wind returns. The tree breathes above them.

Kaeya releases him. Steps back.

“I’m going to duel someone,” he mutters. “I don’t know who yet, but someone. A vision wielder. A god. A bard. Myself.”

Albedo steps forward. Quietly. Steady. Like the sea returning to claim something.

“You didn’t dislike it,” he says.

Kaeya glares. “I hated every second.”

“You blushed.”

“I didn’t.”

“You almost tripped on a root.”

“I was emotionally compromised,” Kaeya snaps.

“You almost kissed me,” Albedo says, voice like an arrow notched but never loosed.

Kaeya’s mouth opens.

Kaeya says nothing.

For once.

They do not kiss. Instead, Kaeya drags a hand down his face and says, “If you say one more word like that I will marry you on the spot and force Diluc to be the flower girl.”

Albedo, blankly: “I see. I will reserve further comments for next time.”

Kaeya screams into his hands.

---

The next morning, the Church of Favonius receives an anonymous request for an emergency wedding booking. It is written in glitter ink and includes the words “ice bastard” and “emotional terrorism.” Barbara frames it.

Albedo logs the results:

Attempt #4: Compliments. Results: Catastrophic success. Subject short-circuited. Almost kissed me. Will repeat with variations. Possibly in the dark. Possibly with cake.

He draws another heart.

It’s bigger this time.

V.

Albedo has, on average, 2.7 ideas per minute.

Statistically, 1.2 of them are dangerous. 0.9 involve Kaeya. And 0.6 are directly responsible for property damage, emotional destabilization, or Kaeya's blood pressure reaching previously theoretical thresholds.

Today’s idea is worse.

Today, Albedo is going to attempt a dramatic exit.

Because if Kaeya's greatest charm is the way he arrives—the way he enters a room like he's seducing it, like he's the answer to a question you forgot to ask, all wind-swept angles and cocked hips and eye half-lidded with deliberate mischief—then Albedo has concluded that the inverse must also hold true:

If Kaeya makes entrances a weapon, then Albedo must master the power of leaving.

Specifically, leaving Kaeya.

Even more specifically, leaving Kaeya wanting.

This, he believes, will grant him what Kaeya calls “the upper hand.”

This, of course, is where the trouble starts.

---

The location is the library.

Kaeya is seated on the edge of the table like a painting hung crooked on purpose, legs crossed at the ankle, scarf coiled at his throat like a sin in silk. He’s flipping through a report he has no intention of reading, occasionally humming something that sounds like a ballad and probably isn’t. Albedo, across from him, is pretending to take notes.

He is, in fact, watching Kaeya.

Observing.

Calculating.

It has been 23 minutes and 47 seconds since Kaeya called him “beloved” in a whisper, entirely unprompted. It has been 22 minutes and 11 seconds since Albedo's brain short-circuited and tried to reboot his emotional firmware with a self-diagnostic error labeled: Attachment Formed (Y/N)? It has been ten years—or it feels like it—since Albedo began this ridiculous attempt at understanding how Kaeya makes people fall in love with him as naturally as breathing.

And now, Albedo thinks, perhaps it is time for retaliation.

He stands.

Kaeya looks up.

Albedo begins, in the smoothest voice he can summon, “I believe I have made an error in judgment.”

Kaeya stills, just a little. “Oh?”

“I’ve spent weeks studying your effect on others. I’ve tested touch, timing, flattery, presentation. But I neglected one variable.”

Kaeya’s smile curls. “Do tell.”

Albedo leans forward. He is too close. He is not close enough. He lets his fingers graze the edge of Kaeya’s knee and watches the reaction flicker in his eye—dilated, startled, interested, wrecked.

Then he murmurs, “The absence of you.”

Kaeya’s breath catches. A pause. A hush.

“I think it’s time I test the inverse,” Albedo says, standing straighter. “Goodbye, Kaeya.”

And he walks out.

---

Kaeya does not move.

Kaeya does not breathe.

Kaeya does not blink.

Kaeya is currently experiencing a full emotional crash, which he does not know how to process, because for the first time in Kaeya Alberich’s stupidly beautiful, aggravatingly flirtatious life—

someone left him first.

---

Ten minutes later, Kaeya is still staring at the door.

Fifteen minutes later, Kaeya is on the floor.

Twenty minutes later, Kaeya has begun reciting Albedo’s last words like a ghost whispering lines from a cursed script.

Thirty minutes later, Amber finds him lying dramatically in the hallway with a book clutched to his chest. When asked what he’s doing, Kaeya mutters something about “loss,” “cruelty,” and “how do you weaponize goodbye like that.”

Amber calls Jean.

Jean calls Rosaria.

Rosaria, unhelpfully, says “Get over it” and hands him a drink.

Kaeya does not get over it.

Kaeya spirals.

---

Meanwhile, Albedo is doing the most dangerous thing imaginable: sitting alone on Starsnatch Cliff, thinking about his feelings.

He has watched clouds form, shift, and vanish again. He has plucked one of Kaeya’s hair strands off his coat and studied its angle of curvature like it’s a sacred relic. He has scribbled in the margins of his journal:

“Test incomplete. Subject reaction unknown. Heartbeat abnormal. Wanted to stay. Didn't.”

He closes the book.

Wind moves around him like a question.

He does not know the answer.

He wants Kaeya to chase him.

He wants to be missed.

He wants Kaeya to feel what he feels when Kaeya vanishes—effortlessly, heartbreakingly, beautifully—leaving only the shadow of a smile behind.

He wants—

No.

He won’t write that part down.

---

Back in Mondstadt, panic has reached a critical threshold.

The following things have occurred:

Kaeya has recruited three patrol squads to help him locate Albedo.

One patrol squad interprets this as a missing person case and ropes in Barbara, who starts a prayer circle.

Another squad reports to Lisa, who offers to find Albedo with “a crystal scrying ritual and a bottle of plum wine,” which Kaeya turns down only barely.

Kaeya goes to the Alchemy Bench. Stares at it. Touches the spot where Albedo once leaned over him during an experiment and murmured, “Your hair smells combustible.”

Kaeya screams into the bench.

Timaeus offers him a health potion.

Kaeya drinks it out of spite.

By evening, the entire city knows Kaeya is “heartbroken and feral.”

By midnight, Diluc sends him a letter that just says, “You did this to yourself. Try apologizing. Or don’t. Either way, shut up.”

Kaeya folds the letter into a paper crane and sends it into the fire.

---

Albedo returns two hours before sunrise.

He finds Kaeya on the roof of the Favonius Headquarters, brooding like a bat with abandonment issues.

“Hello,” Albedo says softly.

Kaeya looks at him.

Albedo waits.

Kaeya stands. He walks over and stops.

“Was it the wind?” Kaeya says hoarsely. “The research? A sudden existential crisis? Or was it just… time to prove your point?”

Albedo doesn’t answer.

Kaeya is shaking.

“You don’t get to just leave, Albedo. Not after that. Not when you say things like that. Not when you—look at me like that.”

Albedo steps closer.

Kaeya backs up.

“You left,” Kaeya says again. “And the world tilted. And the sun didn’t rise. And I forgot how to laugh for seven hours.”

“Did you miss me?” Albedo asks, voice quiet. Open.

Kaeya is trembling.

“I didn’t know how to,” he says. “I didn’t know that was what it felt like. I thought I knew want. I thought I knew absence. I thought I knew loneliness. But I didn’t know you. Not like that.”

“I wanted to test the limit,” Albedo whispers. “To see if I mattered. If my presence could unbalance you as yours unbalances me.”

Kaeya stares at him, stunned.

“You idiot,” he says. “You stupid, perfect idiot.”

Albedo blinks.

Kaeya steps forward.

Albedo does not move.

Kaeya lifts a hand.

Touches Albedo’s cheek.

“Of course you matter,” Kaeya says. “You already won the game. I was yours the moment you tried to flirt using a molecular diagram.”

Albedo’s mouth opens, but no sound comes. He just leans in.

Kaeya does too.

There’s a breath—shared. Warm. Soft. Like a promise just starting to take shape. Their noses brush. Kaeya’s hand slides to the back of Albedo’s neck. Albedo’s fingers grip Kaeya’s coat.

They kiss. Soft at first. Uncertain.

Then Kaeya makes a sound—barely audible, a broken hum in the back of his throat—and Albedo loses all pretense of scientific detachment. He presses closer. Their mouths fit like a proof solved backward—like a question that only made sense in Kaeya’s mouth.

Kaeya tastes like salt and wine and laughter he hasn’t yet had a chance to give. Albedo tastes like snowfall and danger and ink and answers that Kaeya has been trying not to want.

Kaeya pulls back for breath, barely—his thumb brushing under Albedo’s jaw, and Albedo’s eyelids flutter like he’s about to say something catastrophic and tender—

When suddenly:

“ALBEDO, KAEYA, ARE YOU KISSING ON THE ROOF AGAIN?”

They freeze.

A pause.

Then a much closer shout:
“Wait—I knew it! I OWE LISA TEN MORA! Wait, do I have my camera? Sucrose, QUICK—”

Amber. Amber has arrived. And apparently brought reinforcements.

Kaeya and Albedo jolt apart like they’ve been struck by lightning and social obligation simultaneously.

“Do not move,” Kaeya whispers. “They can’t see us if we don’t move.”

“We are not geese,” Albedo hisses back, cheeks flushed, pupils blown wide, lips red from kissing, “and that was my first kiss and I will not have it catalogued by Sucrose’s botany journal.”

“I thought it was my first kiss.”

“You flirt like you have ten ex-partners.”

Kaeya grins, ruined and radiant. “But I’ve never kissed someone who left me in a scientific crisis spiral for fourteen hours.”

Albedo glances at his lips. “Would you like to continue the data collection?”

“I would like to resume it immediately.”

Amber’s voice again: “We’re coming up there unless you make kissing noises!”

Kaeya groans.

Albedo writes later—after hiding for a full hour under Kaeya’s cloak in a supply closet while Amber searched the rooftop with a telescope and half a sandwich:

Attempt #5: Absence and return. Results: Kiss achieved. Interrupted by Amber. Spiritual death occurred. Physical contact confirmed. Subject’s hands extremely warm. Mouth—unknown variable. Further trials necessary. Urgently.

He draws a star beside the entry.

And this time, presses a kiss against the page.

+1.

The problem, as it turns out, is not that Albedo doesn’t understand charm.

The problem is that he does.

He understands it too well now. Like a formula finally solved. Like a dagger finally gripped by the blade. He has observed, tested, failed, nearly combusted, and kissed Kaeya on a rooftop while the sun bled over the horizon and Amber screamed about flower crowns and wagers in the background.

And now, now—

Albedo has data.

Albedo has motive.

Albedo has Kaeya’s attention.

And worst of all—best of all—

Albedo has decided to win.

This time, he is weaponizing it.

This time, Kaeya is the one who won’t know what hit him.

---

It starts in the courtyard. Not at night. Not when Kaeya is used to shadows and sweet nothings spun in the dark like sin on a string. Not when the world is quiet and easy to sway.

No, this happens in the middle of the afternoon, under the full light of day, with a dozen Knights bustling around, too busy to pay attention but not too busy to witness.

Kaeya, striding in like he owns the sun, pauses as a shadow crosses his path. A presence, steady and precise.

Albedo.

Standing beside a training dummy. Holding a rapier.

No coat. Or gloves. Or shame.

Kaeya’s mouth goes dry.

“Join me?” Albedo says, tone clinically neutral, but his eyes. Kaeya would swear those eyes could slice through armor.

Kaeya tries for a smirk. “And here I thought you only dueled with your tongue.”

“Today I’m expanding the arsenal,” Albedo replies, and smiles—and Kaeya stumbles over absolutely nothing.

They spar.

Or, more accurately, Albedo hunts. It’s all elegance and angles, clean cuts and cool gazes, but it’s not about winning. It’s about proximity. It’s about Kaeya parrying a blow only to find Albedo’s breath against his cheek, his mouth a mere breath away, his voice like silk catching on skin as he says—

“Is this how you always disarm people? Or is it just me?”

Kaeya drops his sword.

It hits the ground with a clatter that echoes across the courtyard like a funeral bell tolling for his composure.

Albedo steps closer and leans in. Reaches down—not for the sword, no, but for Kaeya’s scarf, adjusting it like he owns the right, fingers brushing the bare skin beneath.

“There,” he says softly. “Wouldn’t want anyone else seeing this.”

Kaeya blacks out for approximately six emotional seconds.

When he wakes up, he is on the ground.

Albedo is crouched beside him, smiling with teeth.

“You’re flushed,” Albedo says, entirely too calm. “Are you unwell?”

Kaeya tries to sit up. Fails. “You’re doing this on purpose.”

“Yes,” Albedo says simply.

“You’re weaponizing it.”

“Yes.”

“You maniacal, inconveniently beautiful bastard—”

Albedo tilts his head. “Flattery. Noted.”

Kaeya wheezes.

---

It gets worse.

Or better.

Kaeya doesn’t know anymore. He’s in hell. Or heaven. Or some beautiful liminal purgatory where Albedo has suddenly developed the audacity of a man who knows exactly how much power he holds and has decided to use all of it on Kaeya Alberich, specifically.

At a meeting, Albedo passes Kaeya a report on corrosion protocols. The document is irrelevant. What matters is the note at the end.

“Your voice in the morning registers at 122hz. Slightly raspier. I find it distracting.”

Kaeya chokes on his water and has to leave the room.

At Angel’s Share, Albedo shows up in a sleeveless shirt and doesn’t even look at Kaeya once the whole evening. Just sips wine and smiles at the wall while Kaeya melts into the furniture like candlewax left too close to the hearth.

At one point, Diluc leans over and mutters, “He’s doing it on purpose.”

Kaeya hisses, “I know.”

Albedo doesn’t touch him. But every glance is a caress. Every word is a trap. Every quiet hum behind him in the library is a promise. Every time their fingers brush when passing papers, Kaeya forgets how to spell his own name.

It’s maddening.

It’s foreplay.

It’s working.

---

Finally, inevitably, it breaks.

Kaeya finds him in the observatory alone. The stars overhead like gods waiting for the confession.

“Was it all for this?” Kaeya asks, voice low and unsteady. “All those attempts? The scarf? The joke? The compliment? The exit? Just so you could turn it around and ruin me?”

Albedo doesn’t turn.

“Not all,” he says. “The scarf was genuine. The compliment was earned. The exit…” he pauses. “Necessary.”

Kaeya moves forward. “And this?”

Albedo finally looks at him. “This is because I want you.”

The honesty is brutal.

“I want your mouth,” Albedo says, crossing the floor like inevitability incarnate. “I want your hands. I want your noise. I want your sighs. I want your frustration. I want your knees against mine. I want the way you look at me when you’re trying not to fall apart.”

He stops a breath away.

“I want you because you wanted me first. And because I learned—how you look when you’re trying not to hope. How you laugh when you think I’m not listening. How you say my name when you think it’s safe to want something.”

Kaeya is shaking.

“I want you,” Albedo whispers, “and I am no longer afraid of showing it.”

Kaeya doesn’t speak. He just grabs him, and kisses him like the world’s ending and he wants to go out knowing the taste of Albedo’s mouth.

It’s not soft this time. It’s messy. Desperate. Albedo’s hands are in his hair, Kaeya’s palms are splayed against his waist, there’s teeth and breath and pressure and the sound Kaeya makes when Albedo shifts his hips forward should be illegal.

Kaeya pulls back just long enough to whisper, “Say it again.”

“I want you.”

“I know. Say it like a theorem.”

Albedo smiles against his lips. “Kaeya. You are my constant.”

Kaeya growls.

They knock over a telescope.

They make out against the observatory wall like teenagers who’ve just discovered gravity.

Kaeya gets Albedo’s coat off and is halfway through biting down his collarbone when Albedo mutters, “Wait—wait.”

Kaeya stops.

“Am I too much?” he asks, already bracing.

Albedo pants against his ear. “No. I just—” he exhales, flushed, trembling. “I have one more line.”

Kaeya blinks.

“What?”

Albedo kisses his jaw. “Final experiment.”

Kaeya groans. “Are you seriously—”

Albedo leans in. Lips grazing Kaeya’s ear.

He whispers, “Congratulations. You’ve been thoroughly seduced.”

Kaeya laughs so hard he almost falls over.

And then he kisses him again.

And again.

And again.