Sienna | Katsuki Bakugou x Reader
Summary: Based on the song Sienna by The Marías. About an imagined child shaping their choices.
cw: explicit language, relationship conflict, what-if scenarios, sorta slow-burn?
wc: 2.0k
A/n: if there are any spelling errors sorry in advance! <3
Sienna..would’ve been cute, with a temper like you.
You two had been a thing since your last year at UA together.
You had gone out for a dinner since it had been while.
The thought of Bakugou lingered in your mind.
“please tell me not to go..” you slur, something too honest and too drunk for you to process. He laughs, a sharp, ugly bark that you quickly see as soft, and kisses you like he means to mend your heart with his mouth. For the night, it almost worked.
Months later, the joke is a calendar you keep in your folder of the margins.
“You’re so fucking ridiculous,” Bakugou says, hands shoved into the pockets of your shared hoodie as you sit on the roof, the city roaring with sound and colors. His voice is close and low, almost like a rumble of thunder.
“You love ridiculous, katsu,” you answer, trying to sound casual as the world braces for itself for the one thing you never named out loud. He stares at you for a while. Trying to map out in his mind, for a split second he leans in, you say quietly.
“What if we actually…”
“Don’t,” he stops you. Pressing his forehead against yours in that stupid, private way he has and huffs.
“We’re not good at the forever shit,”
“You kept saying that last week,” you pout at him, as you poke a finger to his chest.
“Sure we might be bad at the stuff, but who doesn’t love some disaster,”
He laughs and calls you a brat and kisses you again until the cold makes your teeth hurt. You know Bakugou hates the cold, so being out here makes the excuse of him being clingy better.
You both talked about plans like a harmless rehearsal, what to do if, what to name, silly things that keep the idea of future alive without it sinking in on paper. It becomes a private ritual: a name scratched in the margins, a promise of messy breakfasts, a rule that whoever burns the toast buys the coffee.
Bakugou’s career was reaching its peak, you didn’t really need to go to the hospital much for work since he was doing so well.
Everything was almost perfect for the both of you.
Until the calls started happening. Duty eats away at both of your lives like small efficient blows. More shifts, deployments, villain cases, places you can’t fully see due to the blurriness of the pictures he had sent. He called you from back of ambulances and on roof tops of god knows where.
“I’ll be careful,” he says on the line so often it becomes a litany, almost like a prayer that can’t be answered.
One night, on his two week deployment, he calls you at 2 in the morning. You can see the strain and tension raw as wire through his face.
“you okay, katsu?” you ask, not sure where to begin.
He rubs his temple. “Tch, this shit..it fucking sucks, being without you. from the stupid little life we keep talking about.”
You swallow. “stupid little life.”
“not stupid, just you and your lunatic plans.” he says, voice low with something thats not pride but not surrender either.
“you’re the lunatic katsu,” you roll your eyes. “who the hell says, “we’ll teach them to swear in three languages.””
“Oi, that’s cultural enrichment,” Bakugou protests. He makes a joke about training the kid to be strong, like him. The attempt at normal is fragile and pretty, and it cracks when he pulls his hand over his face.
“I miss being a damn idiot with you,” he confesses. “I miss your damn shampoo and looking at your pretty ass when you ain’t looking,”
You close your eyes. “Then come home, katsuki.”
There’s a pause between the both of you.
“I can’t..always,” he finally says, “sometimes I gotta be where I gotta be. If I don’t go people will be damned, but if I go I got a chance at deaths door and I can’t put that on you.”
“You choose for me like I’m not in the room,” you shoot back, and it hurts because the truth tastes sour on your tongue.
“Thats not—” he stops, because he’s terrible at these kinds of things.
“I don’t want you getting hurt because you’re attached to me, that’s just fucking selfish.”
“Let me make that choice for myself.” You say back, almost a tear falling, you felt that he was pushing you away.
“Baby..I..” his voice got cut as the screen went black. You put your phone down and look at the ceiling.
You sleep with the phone on the couch beside you as you lay on the floor.
Days turn into another: cold coffees, a sweater folded away the way he likes that you never quite manage, the same playlist you both mock now on loop because it sounds like him.
You play his last, half-cut voice "Baby..I.." until it becomes the shape of the hurt.
The first morning after the call you check your messages at dawn. Missed calls, short texts: "Sorry," "Busy," "Later." Each one is an ache that refused to be soothed.
You tell yourself he's at work, that's all. You tell yourself he'll call when he can. You tell yourself a thousand things, and each one feels inadequate.
By the second day, you stop expecting a full explanation. You start to catalogue the small betrayals that add up: a plan canceled without conversation, a shift he forgot to warn you about, weeks of radio scratch updates instead of his real voice. You begin to mourn not the man in uniform but the version of him that used to rehearse domesticity with you on the roof, muttering about ridiculous baby names and stealing your sketchbook.
You mourn the imagined child that had become your quiet metric for whether you two were building anything at all.
Sienna..would've been cute, with a temper like him, run around him..
The sentence slides through your mind and hurts because you picture that small person more vividly than a future with a man who ghosts you.
On the third night, you find yourself on the rood again, hoodie pulled up, breath making little ghosts in the cold. The city hums beneath you. You press the napkin with the doodled tiny person into your palm until the lines blur. You imagine tiny fists and stubborn knees and the way you that child would prefer to shout instead of whisper.
You are doing grief for a life that never existed; somehow the grief is as real as anything.
When he finally shows, it isn't cinematic. It's late. The stairwell light flicks as the doors open and you hear him before you see him. The thundering of heavy boots, the way his silhouette framed by the hallway light, hair plastered to his forehead with rain or sweat, jacket clinging darkly to his broad shoulders. For a breath you are certain you will be furious all over again.
"You can't just...vanish," you say before he can form an apology you'll reject out of habit. Your voice is low, brittle.
His jaw tightens; there's an animal edge to him you haven't heard since the nights he came back from patrol banged up and sleepless.
"Battery died, got rerouted, then locked down," he snaps, but the fury is defensive, fragile. He steps into the apartment and drops his bag with a thud that makes your heart jump.
"I tried to call, okay? I fucking tried."
"You tried?" you repeat, the word like a stone. "You tried and then left me to wait. You made the choice for me. Again."
He flinches as you struck him. For a second you see the man you love, a mess of guily and stubborn pride.
"I didn't want you here when I might..when things go south..I thought-" he breaks off, eyes finding the napkin on the coffee table.
"I thought it was better for you."
"You thought." you laugh, bitter and cold. "You thought for me when I told you I can think for my self, katsuki."
He runs a hand over his face and exhales like someone losing air. "Stop. Listen. I know I fucked up. I know I can be a selfish asshole. But I'm here now, aren't I? I came when I could."
"Why now?" The question is smaller than accusation; it's the only one that matters. "Why tonight."
He looks at you like you're asking him to explain something he hasn't learned to name.
"Because I couldn't stand thinking you sitting here, waiting on a half-message. Because I don't want to be the thing you plan around and then have to mourn." His voice cracks halfway through; he swallows the rest.
You step closer to him until the space between you is only a width of breath.
"Katsu, we said things," you remind him, softly. "We joked about named and futures and all that. I built a life in the margins. I drew a kid on a napkin and gave it our faults." You tap the crumbled paper. "You don't get to decide it doesn't exist by disappearing, especially alone."
He follows your gesture, finger hovering over the napkin as if he's afraid to touch it. For a moment, Bakugou is a boy again, furious,, ashamed, trying yo do the right thing, no one taught him: be small and steady.
"Tell me what you need, baby," he says, raw. "tell me how to not be an ignorant bastard."
You want more than words. You want him to show up in a thousand of insignificant ways that mean you're not alone: to call before a shift, to answer when it matters, to let you make the hard choices with him at your side. You could demand the moon and he'd argue for the stars, but you breathe and choose something both possible and dangerous.
"I need you to include me," you say, hands steady now. "tell me the risks. let me decide if they're worth it. call me when you can. don't make my life a waiting room."
Bakugou exhales slowly, like admitting a weakness is a form of war. "I’ll call," he says, and the promise is small enough to hold and large enough to scare him. "I'll tell you before I take anything that takes me for days and weeks. I'll try not to leave without telling you." He stops, the admission trembling on the edge of everything. "I can't promise I won't go, but I'll not make the choice alone."
You hear the honesty in it, ragged and imperfect. You want to test him, make him fail and then watch him claw back, but the tiredness presses behind your eyes and something steadier than rage settles in your chest. You fold the napkin into your palm and touch it to his knuckles.
"A temper like you," you murmur thinking of the outline of a child who'd steal that exact subborness.
You give him a soft smile as you lean into him. “Run around like you..” you whisper.
He laughs. “Sing like you. Be hella sensitive like you too.” he says. You giggle.
He looks down at you and wraps his arms around you like his own prized possession.
He looks down at the napkin, then at you. For the first time in days his face unravels into peace.
“Let’s plan this shitty parenting workshop together hm?” he says half joke and half plea. he laughs sharp and wet. “I’ll learn to not be an idiot father.”
You let yourself answer with a smile that feels dangerous and true. “Deal. But if it learns my singing we’re both screwed.”
He grins and leans in for a kiss. You go up on your tippy toes and sink into the kiss.
The apartment feels like it can hold absence and the trying.
Outside, the city goes on. Inside, you begin stitching new rules into a life that will be messy and brave.
No more vanished days, a hundred small calls that add up to presence. It isn’t perfect and it will be slow. But tonight, Bakugou is home, and the imagined child, temper and voice remains a quiet mess of what you both want to be.
A/n: this took ALOT to come up with and I really wanted it to be a bit of angst and love. I hope you enjoyed and more stories to come!!
- katsubear <33