🦖 ryusae taking care of bb rin 🦖

eyyyy so i found this really good art of shidou and sae taking care of baby rin

and i was like

AU?

where rin is a baby?

and ryusae are taking care of him?

HELL YEAH

It starts with a mistake.

Well — not really a mistake.

More like...

A cosmic joke at Sae Itoshi's expense.

Because one minute, he's in Spain, minding his business, eating overpriced pastries and ignoring people.

And the next —

There is a baby.

His brother.

In his arms.

Wrapped in a blanket.

Staring up at him with wide, watery teal eyes.

The sitter canceled.

Their parents are gone for the weekend.

There was no backup plan.

So now:

Sae Itoshi is standing in the doorway of his apartment holding Baby Rin like he's a fragile bomb.

Rin blinks up at him.

Then grabs Sae's sleeve.

Tiny fist.

Firm grip.

Sae sighs.

"...Yeah. I know."

He's already resigned to his fate.

The doorbell rings.

Sae regrets breathing.

He opens the door.

Shidou Ryusei stands there with a grin way too wide for a human being.

Pink hoodie.

Piercings glinting.

A bag full of snacks.

"Yo, Sae-baby~ You call and I come runnin'."

Sae stares.

"You invited yourself."

Shidou shrugs.

"Semantics."

Then he notices the bundle in Sae's arms.

His eyebrows shoot up.

"Ohhh. Is that—"

Sae deadpans.

"My brother."

Shidou lights up.

"You didn't tell me we were babysitting!"

"We are not babysitting."

Shidou ignores that.

He leans in, face too close to the tiny baby.

"Heyyy little dude—"

Rin freezes.

Silence.

The world halts.

Their souls clash.

The universe trembles.

Baby Rin squints...

...and makes the most intense expression of pure loathing a baby has ever produced.

He scrunches his brows.

He frowns.

He turns his head away slowly.

Deliberately.

As if to say:

I refuse to acknowledge your existence.

Shidou gasps like he's been shot.

"Huh?! He rejected me already!?"

Sae smirks.

"Good taste."

Shidou sticks out a finger.

"C'mon lil' Itoshi, say hi—"

Rin swats his hand.

Tiny. Angry. Disgusted.

Sae almost chokes.

Shidou clutches his heart.

"He hit me."

"He has judgment," Sae replies.

Rin glares at Shidou.

Like a cat.

A tiny, furious wet-eyed cat.

Rin wiggles in Sae's arms until he's turned completely away from Shidou.

Face buried in Sae's jacket.

Shidou is stunned.

"He's...avoiding me."

"Smart," Sae says calmly, patting Rin's back.

Rin clings tighter to him.

Like:

I have chosen my guardian. You are not him.

Shidou mutters,

"This is discrimination."

Fast-forward twenty minutes.

There are bottles.

Warm milk.

Silicone spoons.

Sae reading instructions off his phone with the dead eyes of someone who has never once read a baby article in his life.

He sits Rin in a little high chair.

Rin looks offended by the mere concept.

He glares up at Sae like:

How dare you.

Sae sighs.

"Open your mouth."

Rin does not.

Shidou leans on the table.

"Try airplane mode."

Sae stares.

"What."

"You know. Vroooom."

He makes plane noises.

Sae wants to leave the planet.

"I'm not doing that."

Shidou grins.

"Then I will~"

He leans close again.

Spoooon.

Airplane.

Silence.

Rin watches him.

Expression flat.

Then—

He slaps the spoon.

Food splatters all over Shidou's hoodie.

Shidou gasps.

"He launched a counterattack—!"

Sae presses his lips together.

Trying not to laugh.

Rin folds his arms.

Yes.

Arms.

Folded.

Like a tiny angry CEO at a board meeting.

Shidou is near tears.

"He hates me..."

"He has instincts," Sae says.

Rin looks smug.

Nap time.

Lights dimmed.

Blanket.

Small baby bed.

Rin...

is fighting god.

He refuses sleep.

He wiggles.

He frowns.

He squeaks in protest.

Sae rubs his forehead.

"I didn't sign up for this."

Shidou crouches beside the crib.

"I got this."

Sae narrows his eyes.

"You'll make it worse."

Shidou grins.

"Trust me."

He leans close.

Soft voice. Gentle tone.

Shockingly calm.

"Hey. Little guy."

Rin slowly...

slowly...

turns his head.

Tiny glare.

Absolute disrespect.

Shidou smiles anyway.

"You don't gotta like me. But sleep is good, yeah? Your brother's tired."

Silence.

Rin blinks.

He glances at Sae.

Sae meets his gaze.

Tired.

Quiet.

Soft.

Rin's expression changes.

Less angry.

More...

worried.

He wiggles his arms.

Reaching.

Sae lifts him.

Rin curls immediately into his chest.

Tiny hand clutching his shirt.

Sae freezes.

Then sighs.

"...You're clingy."

Shidou smiles softly.

"That's cute."

Rin shoots him a glare over Sae's shoulder like:

Do not think this means I like you.

Then closes his eyes.

Slowly.

Peacefully.

Breathing soft and even.

Shidou whispers,

"He really trusts you."

Sae looks down.

Expression unreadable.

"...He always has."

Rin sleeps on the couch now — tiny blanket, tiny fist holding Sae's sleeve.

Sae sits beside him.

Still. Calm.

Shidou sits on the floor, chin on his arms, watching.

"...He really does hate me," Shidou says softly.

Sae glances at him.

"He hates strangers."

Shidou tilts his head.

"So... I'm a stranger?"

Sae hesitates.

Then sighs.

"Yeah."

It sounds heavier than expected.

Shidou doesn't joke back.

He looks at Rin's sleeping face.

Soft.

Calm.

So small.

"...I don't wanna be."

Sae blinks.

Shidou's voice is quiet.

Serious.

"I don't care if he glares or hits me. I wanna be someone that kid can grow up not hating."

Sae looks at him longer.

Like he's reassessing him.

"...Why?"

Shidou laughs a little.

Not wild.

Not chaotic.

Just honest.

"Because people come and go in your life. But family... sticks."

His voice turns light.

Almost fragile.

"And if I'm gonna be around you — I wanna be someone your brother doesn't have to be afraid of."

Sae goes still.

He looks at Rin.

Then back at Shidou.

"...You're an idiot."

Shidou grins.

"Yeah. But a committed one."

Rin stirs.

Tiny movement.

He opens one eye.

Sees Shidou.

Immediate frown.

Instant disgust.

He turns.

Back to Sae's chest.

Sae pets his hair gently.

Shidou sighs dramatically.

"He did it again..."

Sae smirks.

"You'll live."

Evening approaches.

Rin wakes up.

Sleepy-eyed.

Soft.

He doesn't cry.

He just...

Looks around.

Tiny head tilt.

Shidou slowly...

carefully...

slides a stuffed dinosaur toward him.

No big gestures.

No noise.

Just...

offering.

Rin stares.

Suspicious.

Judgmental.

He glances at Sae.

Sae nods.

"It's okay."

Rin looks at the toy again.

Then—

Very slowly—

He grabs it.

Not happily.

Not warmly.

Just...

accepting.

Like:

I tolerate this... sacrifice.

Shidou lights up.

"He took it!"

Sae rolls his eyes.

"He tolerates you now."

Rin turns to Shidou.

Squints.

Points the dinosaur at him.

Then—

BONK.

Light.

Tiny.

Gentle.

He taps Shidou's forehead.

Shidou freezes.

"...Was that... affection?"

Sae shrugs.

"That was violence."

But—

Rin smiles.

Just a little.

Barely.

Shidou's heart explodes.

"HE SMILED AT ME—"

Rin immediately frowns again.

Right back to hatred.

Shidou collapses.

"I lost him."

Sae snorts under his breath.

Rin crawls back into Sae's lap.

Settles in.

Grips his shirt again.

Safe.

Warm.

Loved.

Shidou watches quietly.

Soft.

Gentle.

Respectful.

"...I'll earn it," he murmurs.

Sae glances at him.

"Good luck."

Rin glares at Shidou one last time.

Pure disdain.

Shidou grins back.

Unbothered.

Determined.

Tiny rivalry.

One-sided war.

Kind of family.

And somewhere...

deep down...

Baby Rin decides:

He can stay.

He still hates him.

But maybe...

Just maybe...

Not forever.

art credit: https://www.tumblr.com/bunnyloveroverhere/796179084845760512/ryusae-nation-take-this-sacrifice-suggestion