Chapter Text
It’s Sae’s birthday today. And he dreads it.
Every year he gets a pile of fan mail wishing him well when well they don’t even know him well enough to wish it. Mentally he makes a wish, Please forget my birthday.
Seated in Ego’s chair, Sae watches:
Rin walking across the monitor, clenching his jacket closed, looking side to side.
Sae’s eyes narrow.
Suspicious.
Still tracking Rin—Sae pinches an envelope.
Holds it like it's garbage.
Sniffs it.
The words smell cheap, fake—
It’s all the same.
Something like love. Like:
"I'm your biggest fan!"
"You changed my life!"
"I was addicted to drugs, homeless, and thinking about ending it every hour of every day—but thanks to you I've found soccer. Now I only think about death 10 times a day."
Sae winces.
It reeks of obsession. The counterfeit kind.
He spins in his chair and tosses the letter in the recycling.
Sighs, tired of sifting through the trash for the one gift he actually wants.
The perfect present, handpicked by Sae himself, is lost somewhere in the pile.
Rin vanishes from the camera feed. Only to pop up on another screen, lurking around a corner.
“What is he hiding?” Sae wonders as Ego carts more fan mail into the surveillance room.
“Love.” Ego offers, wistfully.
Sae flinches.
“Probably your birthday present.”
“God, I hope not,” he sighs, leaning back in his chair. “Rin never gets me what I want.”
Since they were kids, Rin had a birthday tradition: be aggressively annoying. Break Sae’s toys faster than replacements could arrive. Then, clever as ever, Rin solved both problems at once—by gifting Sae the toy he wanted instead of the one Sae wanted.
It happened so often, Sae isn’t sure he ever wanted anything to begin with. If he did he’s forgotten.
Sae spins in the chair, following Rin across another monitor. His weird brother keeps stopping to talk to whoever he passes in the hall. But they all keep blowing him off.
Sae almost laughs.
“Idiot has no friends.”
Maybe if he learned how to give people what they wanted.
“He and Isagi were pretty close,” Ego says, tapping the infirmary monitor. He glances at Sae, briefly—eyebrows raised, watching.
Sae doesn’t notice. His eyes are already locked to the screen.
Isagi lies pale and still in the bed, tubes and wires tangled like a cage.
Sae’s lips tighten with dread. He can taste it in the air: latex and bleach struggling to mask iron and rot—it sticks to his tongue like a bad memory stuck on replay.
His eyes stay open anyway, pinned to the scene he’d rather shut away.
“He looks dead,” Sae mutters. He tries to hide it, but the subtle sound of relief leaks out with the words.
Rin's little boy toy is out of commission.
He wants to laugh but quickly swallows it at the thought:
Rin.
His fingers tighten against his thighs.
Pulse ticks a warning he can’t ignore.
Calm down.
He thinks.
Breathe.
But the next part comes out strangled.
Trembling.
“What’s wrong with him?”
“I can’t tell you that. Haven’t you heard of privacy laws?” Ego slides a medical file in front of Sae.
Sae's gaze drops. The file stares back at him, whispering "don't look."
His hand twitches toward it—then snaps back.
Didn’t even realize he’d reached.
A jolt of fear strikes through him.
A flash, an image: his fingers bitten off. Swallowed.
Sae chokes. Rubs his hand.
If he's to survive he needs to know:
What's inside?
What's he hiding?
Finger twitches again.
A pulse hums in his knuckles, electric, insistent.
No, he doesn't need to know. Plus it's against the hippo law to look anyway.
Sae can't break the rule.
Well, he could—but he's afraid of hippos. Mostly their fat asses.
Ego huffs. Flips the file open to a very specific page.
Sae swallows.
Eyes already on the medical records, he reads. Chews his lip as he processes the text.
Thumb traces the edge of the file.
And he tastes blood. Metallic, like being handed a trophy. A victory.
His lips twitch. A smirk, at first…
Oh, looks like the boy toy has already been stress tested—and failed.
Then, realizing what that could mean for him…
His eyes go wide. “No—” he mutters under his breath.
Rin crosses the monitors, jacket clutched like a life preserver. Checks under the stalls before diving into one.
Sae slams a fist on the desk. “WHERE’S THE IN-STALL CAMERA FEED?!”
Ego blinks. Then: “Privacy laws.”
Sae blinks back. Something about that sounds like a personal insult.
Ego leans in. “There is no feed. I’ve thought about it. I even installed the cameras. Some things, though… even I shouldn’t know.”
Sae’s head whips around.
His pulse, a drumline.
His fist still hovers over the desk, shakes, like it’s about to strike again.
But instead he just weakly slaps it.
“Useless,” he hisses, like a cartoon villain deprived of his megalomaniacal plans.
A bead of sweat traces down his temple.
Sae zooms in on Rin’s stall but the door just exists—smug, stonewalling him.
If he waits for Rin to come out, he’ll have already flushed the incriminating evidence.
Instead, he shoves a pile of fan mail into the garbage and storms off.
Rin curses under his breath, loud enough that he feels every mistake echoing around him in the stall. He pulls it out, holding the broken mess in his hand.
It had looked nothing like Rin imagined:
Glass, sleek, perfect and unbreakable.
Straight.
A form that whispers, coolly: Sae.
That’s what it should’ve been.
The scent of cheap rubber and bleach hits Rin’s nose wrong.
He’s seated on the toilet, pants around his ankles, in awe of his carnage.
It’s twisted.
Bent, sitting in the palm of his hands, looking back at him sideways.
Shit.
Sae is going to kill him.
The stall partition shakes around him. A loud pounding rattles the door.
Rin jolts. “What the fuck—it’s occupied?” he growls.
The pounding intensifies.
“What are you doing in there?” Sae calls.
Rin shrieks, throwing his hands up. He tosses the broken toy into the air, tries to catch it, fumbles—it hits the floor and rolls under the next stall.
“Open up, idiot!” Sae shouts.
The door starts shaking as if Sae is trying to rip it off the hinges.
Rin falls to the floor. From the corner of his eye, he sees Sae’s shoes.
The harsh chemical smell assaults him. Blinking away tears, he reaches under to the next stall, scraping at the plastic.
Too far away.
Shit. Stupid thing just came in the mail today. How’d Sae figure out it was missing already?
“If you don’t come out, I’ll just come in,” Sae threatens.
Cheek to floor, Rin stretches out. He catches the plastic’s edge with his finger, pulls hard, spinning the toy closer. Hears the stall door whine on its hinges.
Rin drags it back to his side just as Sae enters. Heart racing, he shoves it under his jacket and wraps his arms around it.
Tight.
Safe.
Sae will never find out.
Rin sighs, relieved. Then looks up like he’s counting his blessings.
And Sae’s staring down at him over the wall.
Shit.
How long has he been there? Rin hunches over, feeling stupid and exposed, kneeling on the bathroom floor.
Sae looming over him like some toilet god, his eyes narrowed, judging Rin.
“What’s under your jacket?” Sae asks.
“Nothing,” Rin twists to the side.
“Better not be some birthday gift,” Sae warns.
“And what if it is?” Rin spits back.
It’s quick—but Rin sees it. Sae’s eyes go wide like his life is flashing before him. Then the door slams shut. Sneakers hit the tile. Squeak. Vanish.
And Rin’s left staring at Sae’s afterimage—guilt clawing at him like the holy ghost wants to crawl inside and force him to confess.
He blinks.
Alone. Heart pounding against the thick, splintered plastic hiding under his jacket.
His arms loosen. Exhales. Safe.
The whole thing had happened so fast, Rin laughs, shakily. The way his heart kicks at his chest, it feels unreal. Sae had been all talk. So what was Rin afraid of?
Nothing.
If anything, Sae’s scared.
The lock clicks sideways. The stall shifts. Rin opens the door, checks over his shoulder, and then—
Something twists inside him.
Wait. Sae’s scared?
A smile creeps across Rin’s sweaty face. He opens his jacket just enough to peek at his secret plan.
“It’s already working,” he mutters to himself.
Sae hurries through the halls of Blue Lock. He would be running but he’s pretty sure Rin knows the sound of his gait.
Paranoid, Sae looks over his shoulder.
He needs to go somewhere where Rin can’t find him.
He tried Ego’s office but it was locked. So now he plans to go back to their dorm and just hide under Rin’s bed.
The hoard of discarded fanfic drafts and half-eaten bagels tells Sae that Rin never looks under there.
When he rounds the corner he gets a phone alert. 99+ new messages in the Blue Lock group chat.
The one everyone talks in the most.
The one Rin isn’t in.
Bachira: hey um why is rin walking around like he just saw god and lost
Chigiri: he’s in his slut era but it’s like. tragic.
Nagi: tragic how.
Reo: HE TRIED TO HIT ON ISAGI
Nagi: ok and? everyone’s tried to hit on isagi
Reo: NO he hit on him so bad he’s in the infirmary
Chigiri: sorry WHAT
Bachira: LMAOOOOO rin speedrunning celibacy%
Tokimitsu: he asked me if i “believed in rebirth”
Kunigami: he told me to meet him in the bathroom with “courage” ???
Reo: LMAOOO NOT “COURAGE” 💀
Bachira: rumor says he’s looking for a “worthy opponent” what is this, a dating shounen?
Karasu: did he really ask everyone though
Reo: everyone but shidou
Shidou: AND I’M OFFENDED. what, i’m not pretty enough???
Chigiri: please don’t volunteer
Reo: shidou bbg u’d say yes
Shidou: it’s called supporting ur teammates 💅
Nagi: imagine ego reading this chat and just closing the laptop
Bachira: ego’s typing
everyone: oh no
Ego: stop gossiping and delete the word “broken” from your vocab immediately
Reo: he saw it 😭😭😭
He scrolls through it, catching keywords his brain is already spiraling over:
Rin. Isagi.
Broken.
Translation: Rin is dangerous.
And Sae is fucked if he's fucked.
Sae enters their shared dorm.
Cautiously. Checks for any signs of Rin.
Then spots his sanctuary across the room—the underside of Rin’s bed, shrouded in darkness. Perfect. He’ll never find him there.
Sae starts toward the bed. But freezes.
A creak, long and painful like a drawn-out moan.
The sound creeps up behind him.
He spins around facing—
Nothing. Just his own bed.
Sae exhales—what a stupid thing to fear.
Then remembers: they already broke their bunkbed. That’s why they sleep separate now.
So yes, Rin could destroy him.
He’s proven it.
Sae glances at his bed one last time, like saying goodbye before joining his new bagel family under Rin’s. But on that final pass—
There, on his pillow, like a cursed offering: Rin’s birthday gift.
He picks both items up. One’s familiar, but… wrong.
A broken toy.
Normally, Rin replaces whatever he ruins. Always some toy Sae didn’t want. Sae would hand it back, no thought. But this—
The shaft twisted, bent, mocking him. Completely wrong.
Sae stares, confused.
This wasn’t what he had ordered.
It’s supposed to be perfect. Sleek. Untouchable.
Instead, it glares at him, cheap plastic screaming failure.
He doesn’t know what to make of it until he sees the second gift.
A booklet titled:
“Rin’s Ass Manual. Handle with care wink wink (haha jk. don’t. seriously. it’s trained to take a beating)”
The bed creaks. Sae is sitting before realizing it. Poring over Rin’s manifesto. The kind that gets leaked online in a broken pdf after Sae’s body is found.
Mangled.
Twisted.
“Please read carefully. This is a training manual on the operation of a WMD.”
Sae brings the manual closer to his face. Focusing on every. Single. Word.
The rules read nonsensical but Sae knows it’s code for how to survive the war.
Don’t look back. If you’re looking back, that means I’m bottoming wrong. Stare straight ahead or look down (and enjoy the view wink wink) or if it’s working look up, pick a god, and curse the day you were born.
Don’t turn around. You’re topping. There’s nothing behind you!
No front facing positions. Unless you’re carrying me like the princess I am. In which case, look me in the eyes as the world crashes down around us.
No eye contact. Absolutely none. Why would you look at my face? My ass is down there!
On page 9 the rule reads:
“Turn back to page 1 and read paragraph 10 before continuing.”
Sae rolls his eyes. There is no paragraph 10 on page 1.
He knows, he’s memorized this manual on first pass.
Maybe this manual is nonsense.
He thinks.
Page 1 ends on paragraph 9 with a random aside about how Rin is like Sleeping Beauty except he’ll be lying face down on the bed and his hole better be destroyed before he wakes.
So, yeah. Nonsense.
Still, like he’s being watched, he flips back to the beginning.
Scrolls down the page, the font suddenly switches to Comic Sans.
“If you’re reading this, congratulations—you’ve already failed Step 1.”
Sae shakes his head. “What? Is this a joke?”
He rubs his back, the spine aches from slouching. The mattress whines like it’s disappointed in him.
What was step 1 again?
“Don’t look back.”
Sae scoffs. He never looked back. Not once. Okay he did flip back to page 1 but the stupid manual told him to.
But that’s only once. Whatever.
Well twice if you count him turning around to find the manual.
Okay, but you’re never gonna find him doing it a third time. In fact, right now, he thinks back on how this whole ridiculous thing started.
Shit!
Okay there’s not going to be a fourth though.
He leans forward. Starts reading the manual again. This time he’s not falling for the trap.
He reads:
“Take me from behind. Make me beg. Make me cry. Make me—”
Wait. Sae freezes.
He heard that.
In Rin’s voice.
Coming from behind him. The bed squeaks as his back stiffens.
Head turns a fraction.
Tempted.
Don’t look back.
Don’t look back.
“Don’t look back.”
The bed creaks. Sae jumps up, spins back around.
Sighs. Relieved.
Whatever he heard, wasn’t there. It’s all in his head. Only thing in front of him now is his bed and the broken dildo.
“What the fuck—I said don’t look back!”
Sae screams tossing the manual over his shoulder. He turns around— He knows Rin’s here, somewhere.
He needs to hide. Now.
A stale bagel rolls across the floor and stops at his foot.
He looks down. The shadow under his brother’s bed quivers.
Mattress creaks.
The words crawl over his shoulder. Breath hot at his ear.
“Happy birthday. Now bend me over and make me squeak.”