Actions

Work Header

Rating:
Archive Warning:
Categories:
Fandom:
Relationships:
Characters:
Additional Tags:
Language:
English
Stats:
Published:
2025-08-25
Updated:
2025-12-13
Words:
33,963
Chapters:
4/?
Comments:
45
Kudos:
46
Bookmarks:
14
Hits:
975

The Somatic Bond Theory

Summary:

“You know what’s weird? I don’t remember learning her name.
I never really called her by it. Didn’t need to.
I just looked. And she looked back.
That was the whole language.”

Or

Dr. Fushiguro Megumi's soulmate was ripped away from him before her 18th birthday.
Now he's 34, teaching about Somatic Bond Theory as a professor under Dr. Gojo Satoru & desperately trying to find her.

Notes:

Hygiene: Don’t repost, lift, or “AI remix” my writing—it’s still mine; & plagiarism will get you banned on both AO3 & Tumblr.

For later chapters: Mixed POVs because I have no respect for structure; & they shift mid-sentence sometimes, so read like you're sipping scalding tea & trying not to spill.

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

Chapter 1: The Summer People

Summary:

Warnings: Emotional Trauma, Psychological Suffering, Soulmate Trauma/Bond Withdrawal, Abandonment Issues, Unreliable Narrator, Mad!Fushiguro Megumi, Maybe Yandere!Megumi, Disappearance of a Loved One, Grief/Mourning, Physical Manifestations of Emotional Pain (e.g., soulmarks burning, twitching), Mild Body Horror (bioluminescent marks, sensory overload), Themes of Loneliness & Longing, Racism against people without soulmarks.

Notes:

Headers are by me.

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

Chapter Text




Megumi leaned back in his chair, arms crossed like a barricade. His gaze wasn’t fixed on anything; it drifted, restless.

 

“You know what’s weird? I don’t remember learning her name.”

 

He spoke like it was an absent thought, something he only realized now. Like the memory was never a moment—just something his body knew, like gripping a spoon, like picking apart fish bones without chewing them. Like how his skin understood hers was the only one it could lean against and never feel itchy.

 

He exhales, a sound caught between a laugh and a scoff.

 

“I never really called her by it. D idn’t need to.

I just looked. And she looked back.

That was the whole language.”

 

He huffed out a laugh, shaking his head. “She was older—seventeen. Smelled like sea salt and oil paints, and sometimes, when she pressed a cold soda can to her wrist, it would glow faintly. Like—” he gestured vaguely, “like bioluminescence or something.”

 

He paused, then smirked, remembering something half-fond, half-infuriating. “I asked her about it once—why her arm did that.”

 

His voice shifted, mimicking hers, lighter, teasing—“‘Same reason yours does, I guess.’”

 

His fingers brushed his bicep briefly, like he was remembering the spot behind his left shoulder blade where his own mark glowed. “No one ever talked about it, not really. But when we walked into a room together, the grown-ups always went quiet. Like we’d tracked sand onto an antique carpet. Like we weren’t supposed to be touching.”

 

He exhaled sharply, letting the memory settle before pushing forward. “But she always smiled at me.”

 

His hand moved to his hair absently, something like muscle memory. “She said it had the shine of stormwater. Made me sit still while she braided it, like it was some ritual.”

 

The corner of his mouth twitched—not quite a smile, but something close. “I let her.”

 

And he didn’t say it, but the unspoken words lingered in the space between breaths.

 

Of course he did.

 

What else was there to do.

 

Megumi exhaled, shifting in his chair. “I grew up in this weird little town by the sea.”

 

He said it like a confession, weighted. “The streets were mossy and cracked. The tide never followed the forecast—it always came in early, like the ocean had somewhere to be.”

 

He rubbed his thumb against his knuckle absently, lost in thought. “People there whispered in circles. My uncle sold gas and always kept a lantern lit, like he was waiting for something. Her mom read fortunes for tourists.”

 

A pause. Then—“But us?”

 

He shifted forward slightly, elbows on his knees, eyes far away. “We had our own world.”

 

His voice softened just a fraction. “She built a fort behind her house with driftwood and orange tarps. That was our summer embassy. I brought notebooks. She brought stolen cigarettes she never lit.”

 

A quiet chuckle, like the memory still amused him. “Told me she was going to be an artist. I told her I’d find dead things for her to draw.”

 

The corner of his mouth twitched—an almost-smile, something old and fond. “It was a pact. A promise. I was sixteen. It already felt too big for my chest.”

 

Silence. Then, “Once, I cut my hand on a broken seashell. She kissed the blood and said—”

 

He tilted his head slightly, voice dipping lower, mimicking hers.

 

‘Your soul’s too loud, Megumi. That’s why the ocean talks back.’

 

He let the words hang for a beat, exhaling through his nose like he was tasting them again. “I didn’t understand it then.”

 

Another pause. “But I remember how she said my name.”

 

His fingers curled against his palm, subtle, instinctive. “Not like a sound. Like a vow.”

 

Megumi exhaled, tapping his thumb against the edge of the table. He wasn’t looking at the person across from him—not really. “Sometimes, when I snapped near her, my back tingled.”

 

His voice stayed steady, but there was something quieter underneath it. “I didn’t even know what a soulmark was back then. Just knew that in the summer heat, when she dozed near me on the bus home, something under my skin would shimmer. Like—” he hesitated, searching for the right word. “Like a memory dying to be remembered like it’s the only thing that mattered between life and death.”

 

There was a pause.

 

Then the person opposite him finally spoke.

 

“So, were you two ever… intimate? The soulmark must have been unbearable in that proximity.”

 

It wasn’t asked crudely, but clinically. Evaluative. As if there was an expected answer.

 

Megumi didn’t respond right away. His fingers stilled over the lip of his water glass.

 

Then he tilted his head slightly. His gaze lifted—not in confrontation, but calculation. The corners of his mouth twitched upward in something not quite a smile. A tick. Like a failed reflex.

 

“You think we could ignore it?”

 

He spoke softly. Without triumph or apology. Just a low, slow echo of an old truth that won’t stop hurting.

 

There had been classifications to these things.

Bond Intensity Grades , listed in columns in academic papers with sanitized acronyms— PBI, SDI, TCS.

 

His and hers had registered as a Tier S Somatic Symbiote Match when they were still teenagers.

 

The kind that lit up cortical imaging like wildfire.

The kind that made the skin warm even through walls.

The kind that made sleep impossible in separation and madness a quiet inevitability.

The kind you wrote about in research but never experienced if you were unlucky.

 

Or if you were the white-haired man.

 

Megumi had spent years studying those patterns in other people. But in his case, it had never been theoretical. His own soulmate mark—first a pale shimmer at the nape of his neck, later a branded flare of bioluminescent sprawl across his back and jawline—had darkened over time. Turned brittle at the edges. Now it looked half-scar, half-something with roots, or just burnt.

 

A wound trying to heal over a ghost limb.

 

Sometimes, he scratched at it in his sleep.

 

But the worst one was the pharyngeal burn—the patch tucked low behind the tendon at the side of his throat.

 

Right where a collar might hide it.

 

Where no one could see how it sometimes twitched when she was near (he’d look everywhere; she never had been) or how it ached when she was not.

 

Even now, as he spoke of her, his fingers drifted up—not to touch the place directly, but just to hover. Like his body was still unable to adjust to her absence.

 

By all means, he should have gone insane by now. It was a miracle, they’d said. After such a bond, it was ‘a big deal’ he was still functional.

 

Megumi wished he was insane.

 

Maybe then being alive wouldn’t hurt. Waking up wouldn’t feel like being cursed into the same nightmare everyday.

 

Or maybe he had already gone insane, and it was all just his imagination.

 

Or maybe just a small maybe she was still...

 

He exhaled slowly for control.

 

“I begged her,” he admitted at last, voice flattening with restraint. “To let me kiss her before she turned eighteen.”

 

There was a stillness, the words settling like dust.

 

“Before her birthday. I told her—just once. So I had something to look forward to. So the next year wouldn’t feel like drowning in turpentine.”

 

His hands tightened slightly—barely perceptible, unless you were looking. Like he was holding back the memory from bleeding.

 

“She wouldn’t let me.” He spat out through gritted teeth.

 

The room stayed quiet.

 

He didn’t offer regret, or resentment, or wounded pride. He didn’t perform heartbreak the way the unbonded imagined it.

 

He just said it plainly. Like a report. Rain again. She didn’t let me.

 

Then, after a pause, his thumb traced slowly across his left wrist—where once, at fifteen, she had painted a line in indigo ink. Not a mark. Not the official one. Just her version of it. Her way of marking him when the universe hadn’t done it yet.

 

She’d said, “It’s a map. So you can find your way back to me.”

 

And she had been right. Even after—no message, no warning—he kept returning to it. In dreams. In research. In the back of lecture halls where his students presented laughable theories about oxytocin cycles and socio-biological impulses.

 

He never corrected them.

 

Because there was no lecture, no journal entry, no chart or citation that could explain the way your throat burned only for one person in the world. The way your skin remembered another’s fingers like they were home. The way absence wasn’t a metaphor—it was a disease.

 

Megumi exhaled, rubbing the back of his hand against his jaw like he was trying to ground himself.

 

“She disappeared the next week.”

 

The words came matter-of-fact. Too sharp to be detached, too controlled to be grief.

 

“The house was locked. Her driftwood fort collapsed in the rain. Her mom’s garden was abandoned, leaves rusting like they were never meant to move.”

 

His fingers tapped against his knee, rhythmic, absentminded.

 

“Nobody told me anything. Just silence. When I asked my uncle, he shrugged and said—” his voice flattened, mimicking, ‘That’s how things go sometimes, kid.’

 

A beat.

 

“I threw up in the alley behind the shrine that night.”

 

He said it like a fact again. Detached, like he’d long stopped feeling real.

 

“Later, I went back to the fort and slept in it alone. The tarps flapped like ghost wings.”

 

He chuckled, but his gaze flickered upward for a second, past the room, past the listener.

 

“Her sketchbook was still there. Half-finished. The last page was a drawing of my back.”

 

His lips pressed together. His fingers curled slightly.

 

“Her fingerprints were smudged into the paper.”

 

Silence stretched, settling heavier than tar.

 

Then his gaze dropped to his wrist. His thumb brushed absently against the skin there—against the mark, the shimmer, the proof that hadn’t faded yet.

Notes:

What do you think happened to her? 👀

Beta: @blackrimmedrose