#sibling fluff

“Engines and Encores”

Pairing: platonic!F1 grid x Sainz!KATSEYE mem! reader

Summary: Y/N Sainz is known to the world as the vibrant, multi-talented maknae of Katseye, one of K-pop’s most popular girl groups. What fans don’t know is that in her rare moments off stage, she’s a complete Formula 1 nerd—thanks to her older brother, Carlos Sainz. When she attends the 2025 paddock as both a celebrity guest and Carlos’s little sister, the drivers are shocked to discover that she can talk aerodynamics and tire strategy as easily as she can nail a dance routine.

WC: 851

Author’s Note (A/N): Tysm for your request and being the first one to do so. I had a lot of fun writing this and I very much enjoy listening to KATSEYE. This is a fun, fluffy, and platonic one-shot about sibling bonds, double lives, and the chaotic energy of a K-pop idol in the F1 paddock. All driver interactions are platonic and supportive. I made up Katseye’s vibe and positions to fit the story.

TW/CW: Mentions of busy idol schedules and media attention, Light teasing between drivers and siblings. Pure wholesome energy

The Double Life of Y/N Sainz

To most of the world, Y/N Sainz was the bright-eyed maknae of Katseye, the six-member K-pop girl group dominating charts with their hit song “Touch.”

She was the one who trended for her cute wink in the encore stage, the one fancams loved because she radiated pure energy, and the one who could switch from sharp choreography to giggly chaos in two seconds flat.

But to her older brother Carlos, she was still the little sister who grew up stealing his karting gloves and memorizing F1 track layouts before she could ride a bike.

During her idol trainee years, while other girls watched variety shows or scrolled social media, Y/N would stream F1 races in secret. Her tablet history was full of things like:

“How does DRS work?”

“Mercedes W12 vs Ferrari SF21 engine comparison”

“F1 tire compounds explained”

Warning: NONE js full fluff, what if you were a tsugoku for a hashira

Gender neutural reader!

(Platonic) hope yall enjoy <3

Giyuu Tomioka :

-At first he will not be comfortable around you at all.

-He would not want to get close to you (But I imagine him with a jumpy Tsugoku who will 10000% annoy him to death until he starts training you)

-When your on missions he will protect you 100% If you get hurt?? Get ready for a hour lecture- Probably wont let you on another mission until your fully 100% healed ;)

-After knowing him for a long time as a Tsugoku he might see you as a little sibling (serious/protective older brother and pure sunshine little sibling probably)

-He will even shield you on missions, since he dosent want to lose another person he cares about

-I imagine you being in the kamaboku squad and nezukos bestie <3333

-Giyuu will SPOIL you. mark my words he will not give a damn about himself but he will do anything for you <'3

Obanai Iguro :

-He will not like you at all the first time you meet him. He will give you glares and turn away from you most of the time since he thinks you are weak and that you will fail on your first ever mission-

-I feel like after a few months he will start to get used to your presence and invite you to meet with him and misturi (You will 100% be besties for ever with mitsuri.)

-If you are a girl I feel like he would dislike you slightly more because of his family, but in the end I feel like you two are going to be the sunshine little sibling and serious, annoying ass older sibling. if you are like obanai and is a big meanie- You will be the perfect duo LMAO

-If you are a boy I feel like if your happy and jumpy then he will be annoyed a LOT. If you are serious like him you two can be the scary ass duo who people fear in all the estate-

-Tsugoku or not he would train you without lots of breaks. not because he thinks your weak but because he secretly cares about you and wants you to protect yourself <3

when you are annoying him, by that I mean somehow you annoyed him so much that he would not care if you were his tsugoku. He WILL consider tying you up on one of the training poles- (Either girl or boy it dosent matter. Rip to yall-)

He will spoil you with a lot of expensive gifts.

You would 10000% bully him about his height. Even if your younger you will be taller probably,,, uh if you even bring up anything about his height.....I will get a funeral ready for yall-

If you get hurt on a mission get ready for you to be ignored. Poor obanai thought you wouldnt make it and ignored you for a whole WEEK because he was mad you werent focused. dw you wont get a hour lecture. you would get a lecture for the whole day-

Mitsuri Kanroji :

-She would LOVE to have a tsugoku

-your going to be spoiled~

-Mitsuri would give you random hugs and 1000 compliments each day

-If you get hurt mitsuri would legit cry and hug you trying to comfort you, (In the end you end up comforting her-) oh and watch out. you have a short angry snake coming at you because you made mitsuri cry-

-Her favorite time with you has to be spenind time with you talking while eating a meal or teaching you breathing styles <3

-She would see you as a little sibling after being her tsugoku for a day- You would also remind her of her younger brother and oml she would be so overprotective of you since she sees you as a family <3

-Now if you are going on a mission by youself (maybe mitsuri is busy or sm) You would need to assure mitsuri you would 10000% come back alive or she wont let you leave </3

-She would never leave you out of her sight since even if your only her tsugoku you are VERY precious to her (lil sibling and sweet protective older sister <333)

Muichiro Tokito :

-At first ofc he kept forgetting who you are T^T He honestly didnt care about you being his tsugoku the first few days

-But still you brought him food and kept bugging him to teach you mist breathing

-After a few months thought he can remember your name at least...that is sometimes-

-If you get hurt on missions Muuichiro would stay by your side until you heal fully. And yes he would have a grudge aganist you for the whole process of treatment

-You would remind him of his twin and he would smile more around you and talk more

-feel like yall two would be the most judgy duo in the whole demon slayer corps :>

-He woul bully you time to time tho (he would act all silly infront of you and tanjiro)

-but on a mission with you? He would brutally kill the demon into shreds :D

Sanemi Shinazugawa:

-ANGRY CHIHUAHUA-

-why did you even get paired up with him?- probably because master kagaya wanted sanemi to be nice to someone for once. I imagine his tsugoku as a ball of sunshine

-You would be realllyyyy close to genya as you see him as a older/younger brother

-Training? It would be hell for you- Sanemi will demand perfection or uh.....looks like no food for you ;) (tho he would js shove a plate of food next to where you are sitting since he would feel bad)

-SOoner or later he would be nicer to you a little bit but thats it ehe~

-if you get hurt on a mission....Genya would be worried sick and would look after you 24/7 while sanemi...he would make sure the demon is dead and gone. he would also lecture you for HOURS

-He wont show it but he does care for you deep inside <3

-But that dosent mean he will be nice to you///

-Rip to your ears. when you are on break I imagine you hearing sanemi screaming at the trainees for the whole DAY

Shinobu Kocho :

-She would be busy with her work but she would make sure you are safe and that you train to become stronger since you are her tsugoku

-Since kanao is also her tsugoku,,,You have a buddy :DDDD

-after trusting you for months she would see you as her little sibling (one of the butterfly member)

-You would be bff with kanao (maybe even help kanao express feelings!)

-If you come home injured......Shinobu would be furious. At the demon and at you for not being safe.

-She would 100% talk about how she couldve lost you and that you should be more careful before she locks you in her estate for the rest of the week-

-She would be the more mature one, she would trust you a LOT (after kanao) and she would make sure to buy you stuff whenever she leaves her estate

-the butterfly sisters will always try and get you to play with them

-I imagine you having a rough past and lost your family (js a hc) so shinobu adopts you as a sibling <3

Tengen Uzui:

-He would see you as a younger sibling and 100% make sure you look flashy in battle js like him </3

-His wives would ADORE you and shower you with gifts lmao

-lowkey imagine tengen getting jealous of your spotlight ;)

-If you get hurt on a mission tengen would lecture you 'Dont put youself infront of others' saying your the number one priority after his wives (since you are his tsugoku and "act like a younger sibling to him")

-He would always do your hair and his wives will make sure you dont have any wounds after a mission

-Tengen would teach you his breathing style and maybe show you off to the other hashiras,,,,I imagine yall hiding your face because of tengen LMAO </3

-but overall under that teasy and flashy expression he cares a LOT about you and if you get hurt very badly,,,,,get a funeral ready for the demon <3

Gyomei Himejima:

-Feel like he would be more like a "father figure" since he is older then most of the hashiras and since he was a kid care taker in a orpanage

-He would introduce you to genya since genya is one of gyomeis trainees

-genya would be friends with you because of gyomei <3

-If you get hurt Gyomei would make you rest for a few days and make sure he teaches you all of the fighting style he knows

-since he lost his "childern" from a demon attack he would shield you in battle and make sure you dont get hurt

-you might be his top priority since he "sees" you as a sibling/child to him

-He would make sure you are feeling okay 100% before letting you train

-overall you would be protected A LOT <3

Rengoku Kyojuro:

(I dont know a lot about him since Im not interested in his character but oh well </3)

-The first time Rengoku met you he immidently introduced you to senjuro and mitsuri

-senjuro sees you as a sibing figure and so does rengoku

-mitsuri will be one of your closest friends

-get ready for a LOT of praises from rengoku and mitsuri

-senjuro and you would be the innnocent but devil duo Lol

-If you get injured in battle, rengokus smile and happy demour would be gone,,,make sure to pray for the demon that hurt you-

-Rengoku would buy you LOTS of things and even introduce you to his father

-suprisingly his father wont be mean to you but still would be strict </3

-Get ready for giant meals with rengoku and mitsuri, sometimes you wonder how they can eat so much T^T

-Every hashira would know you since rengoku will introduce you to EVERYONE 1000%

I hope this is long enough,,,,might make platonic angst for these traumatized fellas :D

Shut up you cornball

Ford Dress-Up Week Day 6- Sleepwear! Aka, the nerds fell asleep prepping a game of DD&MD again. (Bonus: Siblings being siblings)

[Transcript under the cut because Jesus Christ, my handwriting is awful]

Banner by @the-little-moment

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@summer-of-bad-batch | Week #1: “You’re here. You’re safe.” | Bonus Prompt #2: “I am seldom wrong.”

Read here on Ao3

Rated: G | Words: 618

“Tech?” 

The tremulous voice at his back admittedly startles him. More in the fact that the girl must have intentionally walked past their three emotionally intelligent (albeit sleeping) brothers in order to come to the cockpit and find him, specifically. 

an. for I'm in my Sukuita phase <33

Thinking about little Yuji in his Chuku-nii's lap eating a popsicle as his big brother wipes his messy mouth with a caring frown.

Little Yuji is too good to be scolded, always being polite when he points at the icecream shop with big golden-brown eyes looking up at him “Pwes, pwes, Chuku-nii” the highschooler can barely resist the tiny tot's wishes. Although he is a little clumsy with his tiny fingers, struggling to hold the dripping ice and getting some on his school hoodie.

“Tsk, brat. Here give it to me,” Sukuna can be mean to anyone breathing but his little brother. “Suku-nii will hold it for you.” the beaming chubby smile on the five year old almost blinds Sukuna; he swears to god.

-

Baby Yuji triggers the worst cute agression deep within Sukuna (and i take it back, he can be mean) which surfaces in the form of his ever the jerk urge to make Yuji cry so he can scoop his lil pink weeping fluff and sooth him, bouncing lightly. And Yuji not being the sharpest crayon in the box would cling to his chest, pouting while Chuku-nii dries his tear-dampen red face. Sukuna lives for this, wakes and sleeps for his pure innocence.

“There, there. Suku-nii was joking brat, he's not eating you”

“Hah... sorry Yuji, I'm here, are you really scared of jump scares?” a kiss on the fat cheek, chuckling at the little boy's cuteness “I'm here”

-

And apparently it has been way easier to feed healthy meals to little Yuji than him, according to his mom.

“Who's the best boyyy?” Sukuna would drawl and the five year raises his short arm the highest he can, though being the only one being fed in the room. “’tadori!” and thankfully he has learnt to not speak further when the food has been stuffed in his little buccal cavity.

Nothing can make his day better than his little brother looking up at him expectantly with a mouthful of food.

“And who's the best big brother, little Dori?” “Chukunaaa” the elder would chortle, head thrown back because who the heck is more precious than his little petal. Taking the chance, he puts the plastic spoon full of veggies inside him, grin plastered with affection.

masterlist !!

ps. i love babies who have a hard time pronouncing names🥺🤧 shut up you cute lil flower bud

Which, Dick Grayson attempts to bond with his younger adopted sibling, Y/n.

Word count: 2135

Warnings: None.

A/n: This was requested by an anon. The gender wasn't specified, so, the gender is neutral. Hope you like it!

The Wayne Manor was unusually quiet for a Friday evening. The faint hum of Alfred’s vacuum cleaner reverberated faintly from the east wing, while the ticking of the grandfather clock in the study provided a steady rhythm. Dick Grayson sat cross-legged on the plush carpet in the living room, fiddling with the pieces of a half-completed puzzle. It was a rare night off for everyone. No patrols, no missions. Just family time—or whatever passed for family time in this house.

The door creaked open, and the sound of footsteps echoed off the hardwood floor. Dick glanced up, offering a lopsided grin when he saw his younger adopted sibling, Y/n.

“Hey, Y/n,” Dick greeted warmly. “Wanna help me out? I’m starting to think this puzzle’s missing pieces.”

Y/n, with their ever-present hoodie, pulled low over their eyes, shrugged. “No thanks,” they muttered, their voice barely above a whisper. Without breaking stride, they made a beeline for the staircase.

Dick sighed, watching them retreat. It wasn’t the first time Y/n had brushed him off, and he doubted it would be the last. They weren’t close—not like siblings should be. And while Dick could accept that relationships took time, Y/n’s wall of indifference was as impenetrable as the Batcave’s security system.

Jason’s voice broke the silence, startling Dick. “You’re wasting your time, Boy Wonder.”

Dick turned to see his younger brother leaning casually against the doorframe, arms crossed and a faint smirk playing on his lips. “Y/n doesn’t exactly do the ‘bonding’ thing. You should know that by now.”

“I know,” Dick said, rubbing the back of his neck. “But they’re family, Jay. I just… I want them to feel like they belong here.”

Jason snorted, pushing off the doorframe and walking over to the couch. “They belong just fine. They talk to me, don’t they? And Cass. That’s two people. More than some of us got when we first showed up.”

Dick raised an eyebrow. “Yeah, but they don’t talk to me. Or Bruce. Or Damian. Heck, even Alfred barely gets more than a grunt out of them these days.”

Jason shrugged. “Maybe that’s just how they are. Not everyone’s a people person, Grayson.”

“Or maybe,” Dick countered, “they just don’t feel like they can trust us yet.”

Before Jason could respond, the soft pattern of footsteps drew their attention. Cassandra entered the room, her silent presence more comforting than any words could be. She walked over to Y/n, who had reappeared at the base of the stairs and gave them a small wave.

Y/n’s posture relaxed almost imperceptibly, and they managed a faint smile. “Hey, Cass.”

Dick watched the exchange with a pang of envy. Cassandra didn’t need words to connect with people; her understanding went deeper than that. She placed a hand on Y/n’s shoulder and led them toward the couch, where Jason promptly scooted over to make room.

“Great,” Dick said with mock indignation. “Now everyone’s on the couch except me.”

Y/n shot him a fleeting glance before turning back to Cassandra. “You didn’t have to make room for him,” they said dryly.

Jason chuckled. “Told you. They’ve got a sense of humor—just not for you.”

Dick sighed but couldn’t suppress a small grin. “Thanks, Jay. Really helpful.”

———————-

For a while, they sat in companionable silence. Cassandra pulled out a sketchbook and began doodling, while Jason and Y/n exchanged snarky commentary on a cheesy action movie playing on the TV.

Dick watched them from his spot on the floor, feeling like an outsider in his own family. But as the night wore on, he noticed small cracks in Y/n’s icy exterior. The way they leaned ever so slightly toward Cassandra. The way they let Jason tease them without snapping.

Maybe Jason was right. Maybe Y/n didn’t need to bond with everyone in the house to feel like they belonged. But Dick wasn’t ready to give up just yet.

The puzzle piece in his hand snapped into place, and a small sense of accomplishment warmed his chest. Maybe he’d never be the older brother Y/n wanted—but he could still try to be the older brother they needed.

“Hey, Y/n,” he said, holding up the puzzle box. “I bet Jason twenty bucks I could finish this before the movie ends. Wanna help me prove him wrong?”

Y/n hesitated, their eyes flickering to Cassandra for a moment before landing on the puzzle. “Fine,” they said, sliding off the couch and plopping onto the floor beside him. “But if you lose, I’m keeping the twenty.”

Dick laughed, handing them a piece. “Deal.”

It wasn’t much, but it was a start.

Y/n settled cross-legged on the floor next to Dick, their hoodie still shadowing their face. They didn’t look at him as they started sorting through the pile of puzzle pieces, but it didn’t matter. Dick knew better than to push too hard.

“Okay,” he said, shifting the puzzle box to face Y/n. “This is where we’re at. Edge pieces are mostly done. It’s this middle section that’s killing me.”

Y/n raised an eyebrow, picking up a piece and studying it with laser focus. “You separated the pieces by color, right?”

“Uh…” Dick hesitated, scratching his head. “I was getting to that.”

Y/n huffed, a sound that could almost be mistaken for a laugh if Dick didn’t know better. “No wonder you’re stuck.” They pulled the box closer, dividing the pile into smaller groups with quick, practiced movements.

Jason, still lounging on the couch, smirked at the interaction. “Look at that. You’re actually getting them to help. Miracles do happen.”

Y/n didn’t look up. “You’re just scared we’ll finish before the movie ends, and you’ll have to cough up that twenty.”

Jason blinked, caught off guard by the comeback. Then he let out a bark of laughter. “Alright, Y/n. If you win, I’ll throw in another ten just for the sass.”

Cassandra glanced up from her sketchbook, a small, approving smile curving her lips. She didn’t say anything—she rarely did—but her gaze lingered on Dick for a moment, as if to say, Keep going.

Dick took the cue. “Alright, team,” he said, tapping the puzzle. “Let’s do this.”

For a while, they worked in relative silence. Dick occasionally sneaked glances at Y/n, marveling at how quickly they picked out matching pieces. Their focus was intense, almost like watching Bruce when he was in detective mode.

“You’re really good at this,” Dick said casually, not wanting to break the rhythm.

Y/n shrugged. “Used to do puzzles with my mom. She loved this kind of stuff.”

The mention of Y/n’s mother hung in the air like a fragile thread. It wasn’t something they talked about much—or at all. Dick knew better than to pry, but he felt a pang of sadness for the life Y/n had lost before coming to the Manor.

“She must’ve been awesome,” Dick said gently.

Y/n didn’t respond right away, but their hands never stopped moving. “She was.”

The quiet acknowledgment was enough for Dick. He could feel the walls around Y/n shifting, even if only slightly.

By the time the movie credits started rolling, the puzzle was nearly complete. Jason groaned, tossing a pillow in Dick’s direction. “Fine. You win. But I’m blaming Y/n for this betrayal.”

Y/n smirked, holding up the final piece. “I think I’ll take that extra ten now.”

Jason rolled his eyes, digging into his pocket for cash. “Yeah, yeah. Don’t spend it all in one place, kid.”

Y/n pocketed the money with a small but genuine grin—one that caught Dick off guard. It wasn’t much, but it was a rare glimpse of the person behind the hoodie.

“Good teamwork,” Dick said, offering a fist bump.

Y/n hesitated, then bumped their fist against his. “You’re still not getting my twenty,” they said, but their tone was lighter, almost teasing.

Cassandra’s quiet laugh broke the moment, and even Jason cracked a smile.

Dick leaned back, feeling a sense of accomplishment that had nothing to do with finishing the puzzle. It wasn’t perfect, and it wouldn’t fix everything overnight, but for the first time in a long time, it felt like they were moving in the right direction.

As Y/n stood and started heading toward the stairs, Dick called after them. “Hey, Y/n?”

They paused, glancing back over their shoulder.

“You’re welcome to join us anytime. For puzzles, movies… whatever.”

Y/n didn’t respond, but there was a flicker of something in their eyes—something that looked a lot like hope.

As they disappeared upstairs, Jason flopped back onto the couch with a grin. “You’re like a puppy, you know that? Just wagging your tail until someone pets you.”

Dick chuckled. “Maybe. But you saw that smile, right? Totally worth it.”

Cassandra nodded, her expression soft. “They’ll come around,” she said quietly.

Dick smiled, leaning back against the couch. “Yeah,” he said. “They will.”

Bonus Chapter:

The Manor was steeped in darkness, save for the faint glow of moonlight filtering through the grand windows. The clock struck midnight, and the household was mostly quiet. Jason had already retreated to his room with a pile of books he swore he wasn’t reading, and Cassandra had disappeared somewhere in her usual silent way. Bruce and Damian were still out on patrol, leaving the Manor feeling both vast and strangely empty.

Dick was in the kitchen, rummaging through the pantry for a late-night snack, when he heard soft footsteps behind him. He glanced over his shoulder and saw Y/n standing in the doorway, their hoodie pulled up as usual, though the drawstrings were loosened enough to reveal their face.

“Couldn’t sleep?” Dick asked, pulling out a box of cereal.

Y/n shrugged, leaning against the doorframe. “Something like that.”

“Join the club,” Dick said, pouring a bowl. “Want some?”

Y/n hesitated, then nodded. “Sure.”

Dick grabbed another bowl, sliding it across the counter toward them. Y/n moved to the fridge, retrieving the milk without a word. It was a simple routine, but in the quiet of the night, it felt oddly significant.

They sat at the counter in silence, the sound of spoons clinking against ceramic bowls filling the space. Dick stole a glance at Y/n, who seemed lost in thought, their eyes fixed on their cereal.

“You okay?” Dick asked gently.

Y/n shrugged again, a noncommittal gesture that Dick had come to recognize as their default. But then they surprised him. “I don’t… hate it here,” they said quietly, almost as if the words were being dragged out of them.

Dick blinked, caught off guard. “That’s… good to know,” he said, trying not to sound too eager.

Y/n poked at their cereal, avoiding his gaze. “I just… I don’t know how to do this. Any of this. The family stuff. It’s weird.”

Dick set his spoon down, giving them his full attention. “It’s weird for all of us,” he admitted. “I mean, look at this place. We’re not exactly the Brady Bunch.”

Y/n snorted, a small, genuine sound that made Dick smile.

“But,” he continued, “you don’t have to figure it out all at once. And you don’t have to do it alone. We’re all here, whenever you’re ready.”

Y/n didn’t respond right away, but their posture seemed to relax a little. “Jason says you’re too nice for your own good,” they said after a moment.

Dick laughed. “That sounds about right. He’s probably told you all kinds of embarrassing stories about me, huh?”

“Some,” Y/n said, a faint smirk tugging at their lips.

“Well, remind me to return the favor,” Dick said with a grin. “I’ve got plenty of dirt on him too.”

Y/n’s smirk grew into something closer to a smile, and for the first time, Dick felt like he was seeing them—not the guarded, distant version they showed to everyone else, but the person underneath.

They finished their cereal in companionable silence, and as Y/n rinsed their bowl in the sink, they paused. “Thanks,” they said softly, their back still turned.

Dick tilted his head. “For what?”

Y/n shrugged, their voice barely above a whisper. “For trying.”

Dick’s chest tightened, warmth spreading through him. He wanted to say something profound, something to let them know how much that simple acknowledgment meant to him, but all he managed was a soft, “Anytime.”

As Y/n turned to leave, they hesitated in the doorway. “Goodnight, Dick.”

It was the first time they’d said his name, and it caught him so off guard that he almost didn’t respond. “Goodnight, Y/n,” he said, his voice full of quiet affection.