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The first thing Mikasa was aware of was the light. It came through curtains that were too thin. Not the blackout curtains she had always relied on, the ones that kept the world dim and safe when her head threatened to split open. This light was pale gold and merciless, pressing against her eyelids. Her mouth tasted like regret. Her skull felt like it had been repurposed as a percussion instrument overnight.
She did not move. Moving seemed dangerous.
Instead she lay very still and took inventory. She was in a bed. Not hers. The mattress felt unyielding, the sheets too crisp, like they had been washed a hundred times for a hundred strangers. Her body ached in that vague, lingering way that followed a night of dancing, missteps on hard stairs, and one too many drinks. There was warmth at her back. Someone else's warmth.
Mikasa fully opened her eyes.
The ceiling was white and unfamiliar. The room came into focus in pieces. Curtains in a muted copper-gold. A TV fixed to the wall. Evidence of last night scattered across the carpet: one abandoned heel, a crumpled sash that read BIRTHDAY QUEEN in rhinestones, and a half-eaten cake on the nightstand.
She stared at the cake for a long moment.
Then she looked down at herself. Bra. Underwear. Nothing else.
She pulled the sheet up to her collarbone, careful not to make a sound, and turned slowly, her head throbbing in protest, to see who was asleep beside her.
A back. Bare, brown, familiar in a way that didn't require conscious thought. The slope of his shoulders. The faint scar below the left shoulder blade from a camping trip when they were seventeen. She knew that scar. She had cleaned it herself, antiseptic and gauze, while he cursed dramatically and she told him to stop being a baby.
Her mind reached the conclusion before she was ready for it.
Eren.
She sat up too fast and immediately regretted it. The room tilted. She pressed her fingers to her temple and breathed through her nose, slow and deliberate, the way her therapist had taught her for anxiety and which now apparently also applied to waking up in a bed with her best friend while in a state of significant undress.
He was still asleep. She could tell by the rhythm of his breathing, that deep and slightly irritating ease he always had with sleep, like unconsciousness was a place he returned to without effort. Eren had always been able to sleep anywhere. A car, a floor, a library chair. Once, famously, at Jean's cousin's extremely loud house party, in a bathroom.
Her hand lifted before she could think better of it, fingers hovering just short of his back, ready to nudge him awake.
She stopped.
Something caught her attention.
She looked down at her hand. At her left hand.
There was a ring on her finger.
It was simple. A thin gold band, the kind you got from a place that sold jewelry behind glass cases that always looked slightly too bright. It sat on her ring finger with the absolute, settled certainty of something that had been placed there deliberately. She turned her hand over. Turned it back. The ring caught the light.
Mikasa Ackerman was a calm person. She had been described, over the years, as composed, as a little intense, but in a focused way. She did not panic. She assessed, she decided, she acted. Her therapist called it emotional regulation. Annie, her college roommate had called it being slightly terrifying.
She looked at the ring.
A small sound escaped her. Not quite a gasp, not quite a word.
Beside her, Eren shifted. A low, sleepy movement, more instinct than awareness. His arm moved with it, turning just enough.
She saw his hand. His left hand.
The same gold band but slightly thicker than hers settled on his finger with the same quiet certainty.
This time, the sound that left her was sharper. Still contained, but unmistakably there.
She looked between their hands, then at him, something unsteady settling in her chest.
What did we do.
A flash, then. Unbidden and blurred at the edges, the way drunk memories always were. Impression rather than sequence. Neon light. Laughter, both of them, the kind that left your ribs aching. Eren's voice saying something she couldn't quite catch. And then a kiss. Brief. Slightly off-balance. The warm press of a mouth against hers, something she had registered even through the haze because something about it had felt familiar in a way that shouldn't have been.
The memory slipped before she could finish the thought. It left only the echo of it. Warmth without context. A kiss she could not place beyond the certainty that it had happened.
She sat very still in the morning light and tried to decide what to do.
* * *
What woke Eren was a sound.
Small. Barely there. The kind someone made when they were trying not to make one at all.
He knew it anyway. He had grown up with it, learned the shape of it over years, the way it belonged to one specific person who spoke more in restraint than most people did in words.
He opened his eyes.
White ceiling.
His head felt wrecked. His mouth tasted worse. To his side, a woman sat upright against the headboard. Her posture was controlled, but her hands gave her away, fingers tightening and releasing in her lap.
Mikasa.
He blinked at her. She didn't look at him. She was looking at her own hand with focused intensity.
Eren sat up.
Something crinkled beneath him.
He ignored it at first. His shirt was gone. That seemed more important. He looked down at himself, trying to piece together the night in reverse. Then he lifted the blanket and checked.
Pants still on.
He let the blanket fall and exhaled, slow and quiet, something between relief and something he could not quite name yet.
Then the confusion caught up.
Why was he shirtless in a bed he did not recognize. Why was Mikasa here. Why did she look like she was already several steps ahead of a problem he had not even identified.
He shifted.
The crinkling came again.
He reached back and pulled a folded piece of paper from beneath him, slightly creased from having been slept on. He unfolded it. Smoothed it against his knee. Read it once.
Read it again.
Certificate of Marriage
State of Nevada
Eren Jaeger and Mikasa Ackerman.
They had both signed it. His signature was messier than usual, which tracked. Hers, somehow, was still controlled. Clean. Almost perfectly legible.
Eren stared at the paper for a long moment.
Then, and he would admit later that this was the wrong response, freely and repeatedly, he laughed.
It came out before he could stop it. Short. Disbelieving. Because what else did you do when you woke up married to your best friend in Las Vegas, apparently having decided, while drunk, that it was a reasonable course of action.
He turned to Mikasa and held the certificate out to her without a word.
She took it. Read it.
The gasp was audible. Fully, completely audible. The kind she would have been mortified by under any other circumstances. Sharp. Unguarded. The sound of someone who had just had the ground removed from beneath them.
That was what did it.
Eren pressed a fist to his mouth, but it was useless. The laugh came back harder, shoulders shaking, eyes stinging, the helpless kind that came when you knew you were in serious trouble and could not bring yourself to care.
Mikasa turned to look at him. Her expression shifted into something measured. The look she used when she was deciding whether something deserved anger.
"Are you," she said, very evenly, "crying."
"It's," he said, wiping at his eye, "I'm not. It's funny, Mikasa."
"It is not funny, Eren."
"It's a little funny."
"It is not."
He pressed his mouth shut. The laughter had subsided, mostly, though something warm still sat in his chest, something he chose not to look at too closely.
He looked at her. She looked at him. In the pale gold morning light, hair loose and dark, slightly chaotic, wearing nothing but that quiet, stubborn determination, she looked…
He cut the thought off. Looked down at the certificate instead.
"Okay," he said. "Let's figure out what happened."
* * *
The group chat was called Historia's Bday Vegas LETS GOOOO and it had forty-seven unread messages.
They sat side by side on the edge of the bed. Eren had retrieved his shirt from somewhere near the window. Mikasa had found her dress draped over a chair, wrinkled and slightly twisted, as if it had been taken off without much care. They read through the thread in silence.
Sasha had sent a voice note at 1:17 a.m. that was two minutes and forty seconds of her narrating events in real time at a volume that suggested she was standing far too close from Eren and Mikasa without their knowledge.
Okay, okay, they're at the little chapel place, the one with the neon cupid, oh my god, Connie you have to see this, they're filling out the form, they're actually filling out the"
The recording dissolved into laughter and what sounded like Connie saying no way on repeat.
Reiner had sent a photo. Mikasa did not look at it for very long but she registered: neon sign, her own face mid-laugh, Eren's arm around her shoulders, both of them holding small plastic champagne flutes, a man in a slightly wilted tuxedo beaming between them.
Reiner had captioned it: for the wedding album :)
Below that: you're welcome for witnessing btw
Below that, thirty minutes later: actually you two are insane and I refuse to be held responsible
Historia had simply sent seventeen exclamation points and a ring emoji at 2:04 a.m., which was the most Historia response imaginable.
Slowly, like debris surfacing after a shipwreck, the shape of it came back to them. The bar crawl. The fourth round of something blue that Historia had insisted on ordering. The conversation. Whose idea it had been, neither of them could pinpoint, which felt significant.
Exes.
Mikasa had been talking about Porco. About the lack of a clean break. No closure. Just the slow, gradual unraveling of something that had never deserved her time.
"You said you wished you had an ex you actually liked," Eren said slowly, piecing it together.
Mikasa looked at him. "You said it would be funny if we got married so we could call each other ex-husband and ex-wife."
"That," Eren said, "sounds exactly like something drunk me would think was a great idea."
"It sounded like a great idea to drunk me too," Mikasa said, which was perhaps the most concerning thing she had said so far. "So. We get it annulled."
"Obviously."
"We go home, we sort it out legally. This does not have to be a thing."
"Totally."
They looked at each other. Then at the certificate. Then at their rings.
"We are still in Vegas until Sunday," Eren said.
"I'm aware."
He nodded slowly. "So for the next two days we are just"
"Do not say it."
"Technically"
"Eren."
"Married," he finished.
A pause.
And then, because he was incapable of leaving anything alone: "Mrs. Jaeger."
The pillow hit him directly in the face.
He accepted it as deserved.
* * *
Historia Reiss was, in all respects, a woman whose appearance encouraged incorrect assumptions. She was small and blonde and had a quality of light about her that made strangers assume she was gentle. Her friends knew better. Her friends had, at various points, described her as chaotic, unhinged, and operating without fear of consequences, which she took as a compliment.
She had been waiting in the hotel hallway for twenty minutes by the time Mikasa and Eren opened the door.
"I cannot BELIEVE," she said, without preamble, "that you two got married on my birthday and didn't even invite me to the ceremony."
"Historia"
"Reiner showed me the photo. You looked adorable."
"It was an accident," Mikasa said.
"An accident," Historia repeated, her tone making it clear she found this deeply unconvincing. She was looking between them with the brigh gaze of someone who had known them both for a decade and had opinions she had been sitting on for most of that time. "Right. And you're getting it annulled."
"When we get home, yes."
Historia was quiet for a moment. She was doing the thing she did where her expression arranged itself into something reasonable before she said something completely unreasonable. Mikasa recognized the setup.
"You got married," Historia said, "on my birthday, in my Vegas trip, at my party, and you're going to take it back before I've even had time to enjoy it?"
"It's not a gift"
"It's the best birthday present I've ever received and you know it." She reached out and patted Mikasa's hand, the one with the ring, with the gentle firmness of someone making a point. "You're staying married for the rest of the trip. That's all I'm asking. Two days. Then you can do whatever you want."
She smiled. It was a very sweet smile. It was the smile of someone who was going to get exactly what she wanted.
Eren looked at Mikasa. Mikasa looked at Eren.
"Two days," Mikasa said finally.
Historia beamed.
* * *
It was Armin who spotted him first, which was both fortunate and unfortunate. Fortunate because Armin's instinct was always to quietly redirect disaster. Unfortunate because he was too far away to redirect this one in time.
They were at the hotel pool bar, the full group spread out in the afternoon heat, Historia's complete refusal to take anything seriously softening the edges of everything. Mikasa had almost relaxed. She had a drink she did not hate, sunglasses that hid most of her face, and Eren beside her saying something to Connie about a sports team she did not follow.
For a moment, the ring on her finger had stopped feeling like a problem she needed to solve and started feeling like just a thing that was there.
Then she heard her name from the wrong direction.
Porco Galliard had not changed. He had the same easy confidence he had carried all through their two years together, the same good-looking carelessness, the same way of appearing in places without quite belonging. He was with a group she didn't recognize, dressed for the pool, and when he saw her his eyebrows went up and then settled into the slow smile she used to find charming before she understood what it was attached to.
"Mikasa," he said. "Small world."
Her jaw tightened. She was aware, without looking, that Eren had gone still beside her.
"Porco."
His gaze moved past her immediately, and something in his expression shifted. Not surprise. Recognition. He looked at Eren the way people looked at the answer to a question they had already solved. "Of course."
The word carried everything it needed to. Two years of arguments she had not fully understood at the time. You are always with him. It is always him. She had told him he was being unreasonable. She had believed it when she said it.
Eren said nothing. He did not need to. He stood beside her with an easy, unhurried stillness, like he had nowhere else to be. His hand found the small of her back. Light. Barely there. Just the warmth of his palm through the fabric of her cover-up, his thumb moving once, slow and steady.
"So," Porco said, with a smile that did not quite reach his eyes. "You finally stopped pretending."
The silence that followed had edges.
"We are married," Eren said simply. Not a challenge. Just a fact, set down like something that had always been true and had only recently been made official.
Porco let out a short, humorless laugh. The kind that came from being right and not wanting to be. "Right." He looked at Mikasa. Something flickered across his face. The last of something. "Congratulations."
"It is recent," Mikasa said. Her voice came out steady. She was slightly amazed by this.
"Yeah," Porco said. "I bet it is."
The conversation ended the way those conversations did, pleasantries that meant nothing, Porco retreating to his group, and then he was gone and the hand at her back remained for another three seconds before Eren removed it, slow and natural, like it had simply completed its purpose.
Mikasa reached for her drink. Her hand was perfectly still.
Inside her chest, something had come unhitched and was moving in a direction she was choosing not to look at yet.
* * *
The city did not sleep. It did not even slow down. From the balcony on the fourteenth floor, Las Vegas felt like a living thing, restless and lit, the Strip a river of light cutting through the dark.
Mikasa had come out here to think. Eren had come out here, she suspected, because she had. He leaned on the railing beside her with an ease that suggested he would deny it if asked.
They had not talked about the pool bar. About Porco. About the hand. About the word married, placed where it had been placed. They had gone back to the group and been normal at each other with the practiced fluency of two people who had, over twenty-some years, become very good at performing normal while something else moved underneath it.
But it was late now. Quiet. Just the two of them. And the city below made silence feel honest instead of avoidant.
"Thank you," Mikasa said. "For earlier. With Porco."
"You do not have to thank me."
"I know. I am doing it anyway."
He looked at her. She looked at the lights. The thing in her chest that had come loose at the pool was still moving, slow and inevitable, toward something she had been carefully not naming for a long time. Longer than this weekend. Longer than the blurred impression of a kiss she kept circling back to without being able to place it.
"I keep trying to remember last night," she said.
Eren said nothing.
"The kiss." She said it plainly, because she had always been better at plainness than he was. "I remember a kiss. I do not know. It might have been during the ceremony. Maybe that is all it was."
"It wasn't," Eren said.
She looked at him. He was still facing the city, jaw set, the kind of stillness that came when he had decided something and was going to follow through with it.
"Before," he said. "The kiss was before. Outside the chapel. You asked me." He stopped. "I told you something on the walk over. You asked me why I thought the whole thing was funny, the joke about being exes, and I"
He exhaled once, then turned to her.
"I said it was because I figured it was the only way I was ever going to get to call you mine," he said. "Even as a joke. Even drunk. I thought I was being funny. I do not think it came out that way."
The city glittered below them. Mikasa did not move.
"Then you kissed me," he said, quieter. "And then Sasha was yelling about the chapel, and we went inside, and" He stopped. "I do not know how much of that you remember."
A long moment passed. The wind moved between them.
"I remember the kiss," she said. "I did not know it was before."
He nodded, eyes dropping to his hands on the railing, braced for whatever came next the way he always braced, like someone who had learned that wanting something meant preparing to take the hit that followed.
The wind moved through the space between them again.
"I have been," Mikasa said, carefully, "trying not to want things from you for a very long time."
He went still in a different way now. Listening.
"When I was with Porco I thought" She stopped. "I thought if I was with someone else it would go away. That's not a kind thing to admit. But that's what I thought."
"Did it?"
"No."
She turned to face him fully. This was the cost of the late hour and the honest city and the two of them finally running out of places to look that weren't each other.
"The joke was your idea," she said. "Getting married so we could be each other's good ex. But I went along with it because"
She looked at her ring.
"Because even as a joke, it sounded better than nothing."
The wind moved again. Eren turned from the railing to face her, and she watched something in him settle. Not surprise, not quite relief, something older than both. He moved first. One step across the space between them, slow enough that it was a question, and then his hand came up and cupped her jaw, his thumb against her cheekbone, a gentleness that undid the last thing she had been holding carefully in place.
"It's not nothing," he said.
She knew that. She had known it for years, she thought, the way you could know something in your bones without ever letting it become words. She looked up at him in the Las Vegas night and felt, for the first time in longer than she could measure, like something was settling into the right place instead of out of it.
"So we don't annul it," she said.
"I mean." He was almost smiling, that crooked irreverent thing she had been watching for two decades. "We probably should. Eventually. Do it properly."
"Eren."
"I'm saying if we're going to be married we should at least do it on purpose."
She laughed. Soft and genuine, before she could decide to. And she felt him relax at the sound of it, the way he always had, the way her laughing had always landed on him differently than anything else.
"Ask me properly then," she said. "When we're sober. Somewhere that isn't Las Vegas."
"Yeah," he said. "Yeah, okay."
He was still holding her face. She let him. Below them the city kept burning, restless and alive, indifferent to the two people on the fourteenth floor who had managed, by the most improbable route imaginable, to finally get there.
Inside, through the glass, the suite was warm and quiet. The certificate was still somewhere in the bed. The ring was still on her finger.
It was, she thought, a very good joke.
It was, she thought, a very good start.