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English
Series:
Part 1 of A Beating Heart Series
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Published:
2025-04-25
Updated:
2026-01-04
Words:
180,042
Chapters:
56/?
Comments:
97
Kudos:
29
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2,249

A Beating Heart

Summary:

Giving someone your heart means vulnerability, trust, love, and connection. A symbol of letting someone in.

Was that ever true for us?

Or did we not even try?

The heart began to beat.

A steady rhythm—thump… thump—eerily precise. Cold muscle flexed and released like it still belonged in someone’s chest. No blood. Just… alive.

Satoru Gojo dropped it into the box it came in. The wet thud it made was wrong—too alive. It bounced once, then settled, twitching.

Gojo stood frozen.

His blindfold hid his eyes, but his hands—always unshakable—trembled. He’d seen gore before. But this? This was personal.

Kosuke. What are you trying to say?

Was it real? A twisted confession? Was it love? A plea? Or just a cruel joke from the boy he once—maybe—loved?

Gojo’s stomach turned. It wasn’t the sight. It was the intimacy. The madness pulsing in each beat. Kosuke’s heart—still alive, still reaching. It haunted him.

And for the first time in years, Satoru Gojo felt uncertain.

A story in which childhood best friends were separated due to one falling out, only for that one to get in touch 12 years later, hoping to mend something back to normal.

Notes:

Hello! I’m BreadDogsGoodVibez! I go by BreadDog for short. This is my first fic on Ao3 but not my first written. Jujutsu Kaisen has me in a choke hold right now. So I shall throw up some work for you guys. I’ll put Trigger warnings and all that stuff when needed. This fic is gonna be long btw. We gonna plow through it all. Also forgive me for misspelling and wrong facts, the editor is myself and I’m only human :)))

(See the end of the work for more notes.)

Chapter 1: Your Introductions

Notes:

Btw 100k+ fic isn’t bad. Ik my first few chapters aren’t the best… but please hang in there and read it, it gets juicy, it gets angst, it gets fluff, it gets heart wrenching, it gets humorous. If you’re here because of the juicy details between this Kosuke guy and Satoru in the summary, TRUST ME ITS COMING‼️‼️ I’m really proud of this work, so to any new readers, please hang in there🙏🙏

(See the end of the chapter for more notes.)

Chapter Text

5:37 a.m.

Bzzt Bzzt
The infamous white-haired, blue-eyed Satoru Gojo stirred from his ‘princess slumber’ barely an hour in, woken by the persistent buzz of his phone on the bedside table.
Bzzt Bzzt

He rolls over in his bed groaning and cursing wondering who in their right mind would call him at such an ungodly early hour. Now face down in his pillow, his left hand searched the bedside table for his phone which was charging.

Bzzt Bzzt

Following the charger, his hand found his phone and he raised his head, squinting at the light from the phone. He then read the caller ID.

+49 ###-###-####

“What the hell…” Satoru groaned, squinting at the glowing screen in the dark. Two numbers stood out at the start of the phone number—definitely international. “Germany?” he muttered, voice thick with sleep. That only made things worse. He didn’t know anyone in Germany.

Bzzt Bzzt

He hit decline with a lazy swipe and dropped the phone back onto the nightstand with a scoff. Flopping back into the pillow, he buried half his face into it and mumbled something bitter about how his precious sleep was now “tainted.”
Eyes closed. Silence returned.

Bzzt Bzzt

“You’ve got to be kidding me.” This time, Satoru sat up fast, snatching the phone off the table with way more force. His naps were sacred—and timely. Interrupting them has to be a crime.

It was the same number.

He glared at the screen. “Igichi swore the spam filter was airtight,” he muttered. The man had even installed a device to block unimportant calls, claiming only the ‘essentials’ should get through. So if this one was making it past the filter…

Bzzt. Bzzt.

Satoru didn’t answer. He just stared at the vibrating screen, jaw tight. If it was someone real—and not just a very persistent telemarketer—they’d try again.
The phone went quiet.

Then—

Bzzt. Bzzt.

Caller ID

+49 ###-###-####

The phone buzzed a third time.
Satoru groaned, rubbed his face, and finally gave in. He swiped to answer. “Hello?” he said, voice hovering between mock-annoyed and genuinely irritated. “You’ve got some nerve calling me while I’m in the middle of my beauty sleep, you know…”

“Satoru…”

The voice on the other end was quiet—gentle, almost—and carried the kind of relief that felt like a breath after holding it too long. The tone alone was enough to stop Satoru cold. His annoyance faded in an instant.

He straightened up a little, the edge in his voice gone. “…Who is this?”

There was a pause. Not the awkward kind—more like the kind where someone’s trying to find the right words.

“Well…” The voice hesitated, like they weren’t sure how to begin. Then came a soft exhale, like they’d finally decided to just say it.

“This is Kosuke.”

 

“Europe?!”

Two girls stood flabbergasted at the idea of traveling.

“Yep! Germany specifically.” Satoru said, clasping his hands together with a wide smile.

One of the girls turned to the other, eyes wide with excitement. “Oh my gosh, Hasume! Just think of all the tasty food, drinks, and clothes we could buy!” Sumire shook her twin sister’s shoulders with unrestrained enthusiasm.

Sumire, the younger of the two, was a bright and cheerful girl. Her long, snowy white hair marked her as a member of the Gojo bloodline—though she hadn’t inherited Satoru’s iconic piercing blue eyes. Instead, her large obsidian eyes sparkled with an energy that never seemed to fade, perfectly matching her overly happy demeanor.

Hasume quickly pushed her sister back and straightened out her clothes. “That’s exciting and all… but isn’t this kind of sudden? Besides, we’re about to start our first year at Jujutsu High…” she said, her voice calm and thoughtful.

Unlike her energetic twin, Hasume was the more mellow and laid-back of the two. She had short black hair, a sharp contrast to her sister’s snowy white, but shared the other signature trait of the Gojo bloodline—those unmistakable, piercing blue eyes.

“Yes, you’re right,” Satoru said with a grin. “But—” he drew out the word playfully, raising his hands for dramatic flair, “this trip is actually a mission. And you’ll be under supervision.”

He clapped his hands together. “A special grade curse has been spotted in Germany, apparently tied to decades of rising political tension.”

“Outside Japan?” Hasume asked, brows raised.

“It’s rare, but not impossible,” Satoru said with a shrug. “Curses can appear elsewhere. But—” he pointed a finger in the air, “the real reason I’m sending you is to meet an old friend of mine.”

“Who?” Sumire asked curiously.
“Kosuke.”

“No last name?” she tilted her head.

Satoru just shook his head. “Nope. Just Kosuke.”

“Sounds like a weirdo,” Hasume scoffed, folding her arms.

“Hey! Don’t be rude,” Sumire elbowed her sister with a glare.

“It’s fine,” Satoru chuckled. “He is a weirdo. You’ll get it once you meet him.”
He turned back to both of them, voice shifting slightly more serious. “You’ll be leaving in a few days. I’ll take you to the airport myself. Make sure you’re packed—and ready.”

“Ohhh, this is gonna be so exciting!” Sumire practically bounced on her feet, barely able to contain herself.
Hasume, however, had something else on her mind. She leaned in, pulling Sumire aside and whispering, “You do know the legal drinking age in Germany is sixteen, right?”

Sumire blinked, then gave her sister a flat look. “Seriously? That’s what you’re thinking about right now?” she hissed.

“Yeah, duh,” Hasume whispered back. “Who wouldn’t want their first sip of real alcohol?”

A few feet away, Satoru stood with his arms crossed, pretending not to listen—but he heard everything. He sighed inwardly and made a mental note to tell Kosuke: Do not—under any circumstance—let those two anywhere near a pub.

“We should tell Megumi the news! I know he’ll be excited for us!” Sumire said, practically glowing with enthusiasm.
The sun dipped low in the sky as the twins made their way down the path toward Jujutsu High’s entrance, golden light casting long shadows ahead of them. They had plans to wander around Tokyo for the rest of the evening—plans Satoru would probably disapprove of, considering it was getting dark.

“Isn’t he out on a mission?” Hasume muttered, side-eyeing her sister. “And why are you always bringing up Megumi? It’s getting annoying. Besides, he’s not the type to get excited—especially about something that doesn’t involve him.”

“You’re such a mood-killer,” Sumire sighed, pulling her phone from her skirt pocket.
That pocket had been a special request, actually—when Satoru had asked what kind of uniforms they wanted, Sumire had insisted on a skirt and cropped jacket combo. Hasume, more practical, had opted for pants and a standard uniform shirt.

Ignoring her sister’s eye roll, Sumire pulled up Megumi’s contact and started typing out a message.

Sumire
How's the mission going? :)
Delivered 7:34 p.m.

Sumire didn’t get an instant reply, which didn’t surprise her. Megumi was not the type to text back quickly—if at all. And when he did, it was always dry, to-the-point, and about as emotionally expressive as a brick wall. She’d complained about it to Hasume more times than she could count.

With a sigh, she slipped her phone back into her pocket.

In the meantime, the girls found a cozy little ramen shop tucked away in a quiet corner of the street—one of those places that looked unassuming from the outside but smelled like heaven the second you stepped in.

They ordered bowls of Tonkotsu ramen and settled into a booth. The warmth of the broth, rich and savory, melted away the evening chill as they ate.

Halfway through her noodles, Sumire’s phone buzzed.

Finally—a text from Megumi.

Megumi
Still looking for the special grade cursed object.
Delivered 8:25 p.m.

Sumire used her chopsticks to chomp on a handful of ramen before replying.

Sumire
I thought it was in the backyard of some random school?

That’s what Satoru said.
Delivered 8:25 p.m.

Megumi
It wasn’t there
Delivered 8:26 p.m.

Sumire
So are you going to keep looking for it?

It’s already dark…
Delivered 8:26 p.m.

Megumi
No, I’m going to look for it again tomorrow
Delivered 8:26 p.m.

Sumire
Well good luck 🙃
Read 8:27 p.m.

Sumire groaned, staring at Megumi’s reply like it personally offended her. Dry. One-word. Zero effort.

She slumped back in her seat, muttering to herself. “I swear, I should teach a class on how not to text like a robot. This is exhausting.”

Yeah, she was definitely bringing it up once he got back from Sendai.

The next day rolled in like usual.
Satoru was off handling missions and getting things in order for the upcoming school term. Between assignments, he sent the girls a list of tasks—nothing crazy, just a couple low-level missions and odd jobs the higher-ups wanted handled. The kind of stuff he’d rather not deal with. Luckily, Sumire and Hasume didn’t mind picking up the slack; if it lightened Satoru’s load, they were in.

Throughout the day, Sumire kept checking her phone for updates from Megumi—any update—but he was still radio silent.
Nothing came through… until around 10 p.m.

The twins were in their separate dorm rooms, both stretched out and half-distracted on their phones when a message popped up in their group chat from Satoru.

‘Look how beat up he got while fighting a curse!’

Attached was a picture of Megumi—bruised, bloodied, and looking like he’d lost a fight with a freight train.

Sumire
What happened to him?!
Delivered 10:09 p.m.

While Sumire gave the general worried response, Hasume felt a little mischievous

Hasume
Did the curse even touch him or did he just trip down a flight of stairs??
Delivered 10:09 p.m.

Sumire
HASUME RUDE
Delivered 10:09 p.m.

Satoru
HAHAHAHA IM GOING TO TELL MEGUMI THAT

He tried fighting a grade two curse but it was pretty powerful.

Though something interesting did happen 😉
Delivered 10:10 p.m.

Sumire
What was it?
Delivered 10:10 p.m.

Satoru
I happened to be in Sendai and decided
to visit Megumi on his mission, but this kid
named Yuji Itadori swallowed the special
grade cursed finger Megumi was searching
for and the curse reincarnated within his body.

Luckily it was no match for me.

He’s out cold in the back of Igichi’s car and I

can hear Megumi grumbling about your
comment I told him about 😁😁
Delivered 10:11 p.m.

Hasume
Good >:)
Delivered 10:11 p.m.

Sumire
I hope Megumi is okay
Delivered 10:11 p.m.

Hasume
Wow seems interesting

What will you do with him?
Delivered 10:11 p.m.

Satoru
Because he reincarnated that special grade
curse, he’ll be executed but Megumi wanted him to live. So my compromise is to let him locate the rest of the cursed fingers and then
execute him.
Delivered 10:12 p.m.

Hasume
Sounds pretty sad, but I’m glad you delayed his death
Delivered 10:12 p.m.

Sumire
So will he be joining jujutsu high?
Delivered 10:12 p.m.

Satoru
Yep! He’ll be a new student! 🥳🥳
Delivered 10:13 p.m.

Hasume
Wow so we’ll have five in the first year class?
Delivered 10:13 p.m.

Satoru
Even bigger than my graduating class!
Delivered 10:13 p.m.

Sumire
Can’t wait to meet him!
Delivered 10:14 p.m.

Even if the reason for this “Yuji” guy coming to Jujutsu High was… complicated—and probably doomed to end in his execution—the girls couldn’t help but feel a little excited. It wasn’t every day they got a new classmate, and honestly, having more people around sounded like a nice change of pace.

 

The next day, Megumi—fresh from being patched up by Shoko—stopped by the crematorium to check in on Satoru and Yuji. Things moved fast after that.

By afternoon, Yuji Itadori had officially arrived at Jujutsu High.

Now that Satoru was finally back from his cross-country work spree, the girls saw their opportunity.

And naturally, they decided this called for something important. Something bold. Something dramatic.

Their grand entrance.

“Woahh!! This place is huge!” Yuji’s voice echoed through the dorm room as he darted from corner to corner, poking, pulling, and fiddling with everything that wasn’t nailed down. He was clearly making himself at home—already pinning up one of his girl posters with enthusiasm.

Satoru leaned casually against the doorframe, watching with an amused look. “All the second and third years are out at the moment. But you’ll meet them all soon enough. There aren’t many of them,” he said, tone light. “Y’know there isn’t any real reason for you to fight at all~” he teased with a grin. “Fushiguro and I could retrieve all of Sukuna’s fingers and you just stay here and chill out.”

Yuji scoffed, plopping down on his new bed with a bounce. “Yeah, nice try guy. I said I’d do it, and I will. Though I gotta say, hanging out until Fushiguro comes back all beat up just to bring me a finger. Haha, that’d be funny!” The image clearly amused him—he laughed to himself, shaking his head.

Satoru smirked knowingly. “Yeah, but you wouldn’t have refused to fight. I already knew that.”

“Huh? That was a test!?” Yuji shot up, fist raised in protest.

Satoru stepped further into the room, walking with that usual carefree swagger, and pressed a finger to Yuji’s lips. “If the fingers were that easy to find, don’t you think we would have collected them all by now?” he said, his tone suddenly shifting into something sharper—like he was explaining the obvious.

He took a step back and continued, “Some have a presence that’s overwhelming, some keep very quiet, and some have already been absorbed by cursed spirits. These are the challenges we’ve dealt with when it comes to searching for them. But! At last we have you.”

With a grin, he poked Yuji in the chest. “The Sukuna within you will try to regain power. And that will lead us to the fingers. You’re both vessel and locator. Our very own radar! So you see? We won’t get very far without you.”

Satoru straightened up again, arms folded, confident as ever.

Yuji glanced down at his chest, brow furrowed. “Are you sure he’s going to be that cooperative?”

“Oh I think we can come to a win-win agreement there,” Satoru replied with a laugh—right as he casually stole Yuji’s slippers like it was the most natural thing in the world.

The two of them strolled out into the hallway, only to see Megumi’s door swing open as he stepped out.

Megumi’s expression immediately twisted into something between disbelief and disgust. “You’re next door?”

“Hey! Fushiguro! Wow, you look all better now!” Yuji greeted him with a bright, clueless smile.

Megumi ran a hand through his hair, already looking like he regretted leaving his room. This new guy’s energy reminded him way too much of someone else he knew—someone who routinely gave him a headache. “There’s lots of other empty rooms, y’know…” he grumbled to Satoru.
But both Satoru and Yuji kept walking toward him undeterred.

“Sure, but isn’t it better to have some company? I thought I’d be good for—”
“Classes and the missions are enough…” Megumi cut him off flatly. “This is not welcome.”

Yuji peeked into Megumi’s room despite the very clear boundaries being set. It was spotless—like, hospital-room clean. Everything was perfectly arranged and completely impersonal. Not a poster, not a single sign of life beyond basic function.
“Wohoah, it’s so organized here!”

Megumi didn’t miss a beat. He grabbed the door and hissed, “Back off, I just told you you’re not welcome!” Then slammed it right in Yuji’s face.

Yuji winced and rubbed the back of his head, lips forming a defeated pout.
“Ah! Friends already!” Satoru clapped his hands together with a big grin. “And together we’re heading out tomorrow! We’re going to pick up the fifth and final first year!”

“Fifth? Wait… if it’s me, Fushiguro, and this other person, then who are the other two?” Yuji asked, brow furrowed.
Right on cue, a sudden surge of cursed energy whooshed down the hallway like a warning shot. A glowing yin talisman appeared above Satoru’s head.

“Oh, come on—” Satoru muttered, turning to flee. But his slippers betrayed him, sliding uselessly over the polished wooden floor. Before he could recover, Sumire lunged from behind, arms and legs wrapping around him like a koala.
He sighed, already resigned to his fate. “Really?”

“Heya!” Sumire grinned, hopping off him and stepping out with Hasume in tow.
Yuji blinked, caught off guard by the sight of the two girls. They were… actually pretty cute. Way cuter than anyone from his middle school. His brain short-circuited for a second.

Megumi groaned. “Pick your jaw up. Those are Gojo’s daughters.”

Yuji snapped out of it, flustered. “Wait, daughters? Aren’t they kind of—how old are you, Gojo—?”

Whack. Megumi smacked the back of Yuji’s head.

“Ow! What’d I say?!” Yuji glanced at Megumi.

“Be respectful,” Megumi hissed through gritted teeth. “God, this is so embarrassing…”

Sumire laughed, clearly entertained. “He’s kind of funny.”

Hasume, however, just gave Yuji a once-over and raised a skeptical brow. Immature, she thought.

Satoru gave a dramatic flourish, clearly enjoying the attention. “As Megumi so helpfully mentioned, these are my daughters. That’s Sumire—” he gestured to the tall, white-haired twin, “—and Hasume,” he said, pointing to the shorter one with jet-black hair.

“Oh! …Their names seem pretty easy to mix up…” Yuji said, tilting his head as he looked between the two girls.

“It’s not that hard once you’ve been around us for a bit,” Hasume replied coolly, arms crossed as she shot a glance toward Satoru.

Satoru, meanwhile, was practically vibrating with excitement. “The team is almost complete! I bet the second years are gonna be so jealous with how many first years we’ve got!”

He was way too enthusiastic about it—for Megumi, anyway. He just stared at Satoru with a deadpan look that screamed please calm down.

They were going to go see the last and final first year anyway… how is that exciting?

Notes:

Woweee! My first chapter yippieee I hope you guys enjoyed it as much as I written it. Ik I teased Kosuke cause he gonna be very relevant within the next chapters when the girls go to Germany :)))