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Origin Story

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Some people claimed that they saw red, but Gaku never did. Instead, when emotions began to curdle in his gut—when jealousy and hate threatened to come pouring off his lips like sludge—all he could see was black. He could taste it in the corners of his mouth, sitting tucked under his tongue; could feel it, buried under his fingernails, itching to dig in and tear. It twisted and tangled his veins into knots under his skin, squeezing whispered promises out of his bones.

When Satoru was there—when Satoru was threatened—it exploded, like a tidal wave rushing over his senses.

But right now, in the comfort of his classroom, it just left him blank.

The mask of apathy sat heavy on his skin, a familiar disguise in the crowd of bored children. Gaku played the role of the dutiful student; he answered when called upon like he always had, sharing polite smiles with his classmates. It was little more than auto-pilot at this point: he moved like a tin soldier, aimlessly marching forward on rails towards nothing.

But it left his mind free. So as he stared down at his notes, Gaku sank back into his own head, allowing the black ocean to swim in front of his eyes. All too eagerly, he sank into the depths, feeling the cool, furious calm overtaking his senses. His pencil tapped against the page, his eyes hollow as they stared into nothing.  

Still, those two words rang in his ears.

New friends. New friends. New friends.

A feedback loop of the worst kind. Gaku forced himself to breathe past it, his eyes narrowing. Something in him was snarling and snapping its teeth, straining the chains of his self-control—but that didn’t mean he had to let it loose. Not yet.

No, if anything, it was the opposite: Gaku’s mind was, for the most part, calm—even like a perfect sheet of glass. Gifted with the time to think, he pretended to follow the lesson; but his brain was busily ticking through actions and outcomes, clicking through the gambling chips in his skull. A slight of hand, a bluff and a well-placed lie; every situation had risks and rewards, but there was always a solution. This was no different. He just needed to find it.

Present situation: Satoru would be making new friends—if he hadn’t already.

Desired result: for it to be just Satoru and him, forever.

Gaku could still see the crowds cramming through the kindergarten gate, dozens of threats children pouring out through the doors. Even if he managed to isolate everyone in Satoru’s class, there would still be the rest of the grade to worry about. And that was just this year: soon Satoru would be starting elementary school, and then middle school, and beyond. There would be no simple way to get the message across to all of them, no easy method to make sure they all stayed away.

Gaku paused, his pencil lying still against the page.

A smirk spread across his lips as he stared down at his notebook. It was so obvious, so simple, why hadn’t he seen it before? Satisfaction bled out of his bones, and Gaku brought his thumb to his lips, sinking his teeth into his own skin. Pain flared, and he let it bloom and spread, adrenaline rushing like a drug through his blood. 

He couldn’t get the other kids to stay away from Satoru. But he didn’t have to.

Not when he could do the opposite.



For the second time that day, Gaku found himself standing outside of Satoru’s school. Impatiently, he paced back and forth, his arms crossed and finger tapping against his elbow. Their schools officially let out at the same time, but Gaku was quick and efficient—especially compared to a bunch of five-year-olds. He managed to arrive just as the first few students were beginning to trickle out the doors.

Every so often he could spy a duck hat—often clustered with others like it, classmates gravitating together in a sea of strangers. Gaku’s eyes swept over them, before quickly discarding them from importance. They weren’t Satoru, and thus, they were disposable; nothing more than useless clutter that clogged his way.

But he continued to watch the door with a forced patience, irritation bubbling in his blood.

A pair of ducks began to hop their way down the few cement steps—and Gaku felt himself snarl.

Satoru laughed like a ringing bell, his face bright and trusting and looking at someone else. The girl at his side was chittering along like an idiot, one hand moving wildly to demonstrate whatever nonsense she was stuffing his head with. But the other was firmly wrapped around Satoru’s palm, their little fingers tangled together. Her hand squeezed his as she dragged him across the yard, and Gaku watched in horror as Satoru blushed, his entire body going stiff.

Whatever calm rationality had settled over Gaku shattered. Every instinct was screaming to go over there, to rip them apart, to make sure she never so much as thought about—

Blue eyes met his. “Gaku-nii!”

Gaku’s face burst into a smile. Satoru dropped the girl’s hand immediately—and something in Gaku preened, smug and relieved. His knees hit the pavement as Satoru ran towards him, his duck hat falling forward in front of his face. The boy blindly crashed into his chest, and Gaku couldn’t find it in him to chastise him; he just swallowed a laugh and wrapped one arm Satoru, the other gently tugging the hat back into its proper place. “Hello again.”

“You came to pick me up!” Satoru beamed.

“Of course. I wouldn’t miss it for the world,” he promised, poking Satoru in the cheek. “Are you ready to go?”

“Uh-huh!” he squirmed in Gaku’s grip until he was twisting around, waving wildly. “Bye-bye, Atko! See you tomorrow!”

The girl from before turned away from her own mother. Her eyes found Satoru first, before wandering up to Gaku’s face, tilting her head. His fingers twisted tightly into Satoru’s coat, already pulling Satoru closer, locking him in his arms. A flicker of something flashed across her face—but then she gave a small wave back, clutching at her mother’s hand. “Bye-bye, Satoru!”

They turned to walk away, and Gaku watched them go, a silent roar shaking under his ribs. Only when they both had passed the gates did something in him ease a little bit, the rabid beast in his head simmering down to a hum. His tense muscles loosened their grip, and his clutching hands turned soft, gently patting down the wrinkles in Satoru’s clothes.

Satoru’s eyes were looking his way, all his attention and affection offered up on a silver platter. “I drew a cat!”

“Oh, really?” Gaku said, pushing himself to his feet. Playfully, he flipped up the bill of Satoru’s hat. “Not a duck?”

“No! A cat!” he huffed, pulling his hat back down with a pout. Gaku held out his hand, and Satoru immediately grasped at it, his little fingers wrapping around one of Gaku’s own. “I wanted to make him green, but someone said cats can’t be green, so he’s orange now.”

“I’m sure it’s very handsome.” Gaku eagerly tugged Satoru back out towards the road, a little faster than he’d intended, but his feet refused to slow down. Not until they were far away from the children and the people who would try to come between them. But Gaku still forced a smile, baring his teeth as his hand squeezed Satoru’s palm. “Why don’t we get some ice cream, and you can show me?”

“Ice cream?” Satoru exclaimed, half-jogging to keep up with the older boy’s faster pace. “Really?!”

“Why not? It’s a special day. We should celebrate.”

“Can I get chocolate sauce?” Satoru pulled at his hand, his expression serious. “Mama says I’ll just make a mess, but I won’t!”

Gaku gave a low hum at that. God knows he’d seen Satoru eat before—or, his attempts at eating, more like. There were probably raccoons who could manage to keep more on their plate. But Satoru was staring up at him with those big blue eyes, his fingers still squeezing at his hand—and Gaku knew he’d already lost, heaving a resigned sigh. “Okay,” he said, holding up a finger, “but, only a little. And you have to eat it in a bowl.”

Satoru’s face bloomed into a smile. “Yay,” he whispered to himself, his other hand pumping a little victorious fist. Facing forward, Satoru began to happily jump from line to line on the crosswalk, his mouth babbling everything that came to mind; Gaku happily lost himself in the sound, running his thumb along the back of Satoru’s hand.

They didn’t need anyone else.

Satoru just needed to understand that, too.



Of course, the bowl really didn’t help. Gaku frowned, wetting a napkin with his tongue. Immediately, Satoru tried to squirm away from it—so he gently took hold of the boy’s chin, holding his head still. There was brown fudge sauce smeared all over and around Satoru’s mouth, but Gaku had at least expected that to happen. That was normal, at least by Satoru’s standards. But this—

Gaku sighed, rubbing behind the boy’s ear. “How did you even get chocolate back here?”

“I ‘unno,” Satoru shrugged, shoveling more into his mouth. His feet swung back and forth from his spot on the park bench, his fingers sticky with fudge; Gaku kneeled in front of him, one knee on the ground as he rubbed at Satoru’s cheeks in vain. The boy’s tongue darted out to lick up the extra cream, but he only managed to smear it around.

His spoon moved far too slowly for Gaku’s liking, the melting ice cream piled dangerously high. “Careful,” Gaku tutted, catching a string of fudge in his napkin. He narrowed his eyes, before flicking at Satoru’s nose. “I’m starting to understand why your mother doesn’t let you have this.”

Satoru gave sheepish smile as he swallowed another bite, murmuring quietly around his spoon. “Thank you for ice cream, Gaku-nii.”

He couldn’t help but smile back. When Satoru looked at him like that—when his face was open with simple trust and adoration—the shadows in his soul were banished away, thrown off his shoulders and into the wind. Nothing else could make him feel that way. Nothing else could make him feel, at all.

He wasn’t going to share that with anyone.

“Well, that’s what friends are for,” he said, dabbing at Satoru’s lips again. “Speaking of which, Satoru… who was that girl you were talking to?”

“Atko!” he chirped, his entire face brightening—and the thick, acrid loathing in Gaku’s gut churned, throwing itself against the dam of his self-restraint. “She’s nice and likes Precure, which I told her isn’t as cool as Wonder Guy because it isn’t,” Satoru pointed out, his lips twisting into a pout. “But she said they look prettier, and—”

Gaku pressed the napkin to Satoru’s lips, his eyes cold as ice.

“Is she your friend?”

Satoru blinked down at him, blissfully oblivious. “Yeah!”

Gaku’s free hand snapped into a sudden fist. His knuckles cracked and popped, his fingers squeezing until the blood welled up under his nails. Somewhere inside, that beast, rabid and foaming at the mouth, snapped free of its chains; the dark intent flowed freely through his veins, leaking out of his bleeding palm.

Every instinct was telling him to follow the feeling: to find that stupid little girl and smash her skull into the pavement. He wanted to hear that satisfying crack again and again until all that was left of her were little pieces of shattered bone, scattered like eggshells at his feet. He imagined her empty brain smeared across the concrete, bloody grey on grey—and he let out a shuddering breath, his body aching with want.

(Then, when all was said and done, he could grab Satoru and run: never letting go, never stopping, never found.)

His fingers twitched.

(He could do it.)

Gaku took a deep breath, and slowly dropped his hand from Satoru’s face.

(But not yet.)

Instead, Gaku did what he did best. He lied.

The charade was easy, the moves rehearsed: the slight downturn on his mouth, the way his gaze dropped, the dip of his voice into something quiet and soft. Gaku swallowed down a thickness in his throat that wasn’t there, and he slipped the napkin from one hand into the other, pressing it against his bloody palm. “I… I see.”

Satoru watched for a second, before his eyebrows furrowed, his bowl and spoon set down in his lap. “G-Gaku-nii?” he asked, scooting closer. “Wha—what’s wrong?”

“Oh,” he murmured, pretending to look sheepish, even as crocodile tears sprung to his eyes. “Well, if you’re friends with Atko, then you will start playing together after school. You won’t be able to play with me anymore.”

“I-I’ll still play with you, Gaku-nii!” Satoru assured him, his own voice rising with thinly-veiled panic. “Atko will only be a sometimes friend!”

Gaku’s entire body twitched at that last word, that familiar hate surging up his throat—but he stamped it back down, burying it under his skin. Not now. Gaku just needed to go a little bit further; it was so close he could almost taste it, thick like the sweetest honey he would ever know. His thin smile wobbled on his face, and he sniffed through his nose.

“I-I know,” he said, his voice thick. “And when you’re playing with Atko, I guess I’ll just… go home.”

Then, he placed his hand on his own arm, and winced.

Satoru’s eyes widened. Gaku suppressed a grin.

“A-and—and you’ll get ouches?” Satoru whispered.

Gaku opened his mouth, prepared to spit the prepared lies, but Satoru was there first: surging forward, sticky hands grasping at Gaku’s coat. His face was a pale caricature of itself, twisted by guilt and pain. Tears were already starting to stream down his cheeks, dripping off his chin. His little fingers were shaking, but wouldn’t let go: too frantic, too terrified to do anything but cling on, his breaths trapped and tangled in his chest.

“B-but, but that’s not wh-what I—I didn’t want th-that, G-Gaku-nii—!”

The boy’s words were suddenly swallowed by his sobs, his voice little more than an anguished wail. Gaku never liked seeing Satoru upset—but he would be lying if some part of him didn’t savour this, seeing the depths of Satoru’s devotion on full display. It was like a feast for the hungriest part of his soul, and Gaku couldn’t help the pleased sigh that just barely slipped out of his mouth.

His hand landed on Satoru’s head, his fingers slipping through the soft strands. “Shh,” he whispered, a soft smile on his lips. His arms wrapped around Satoru, gently tucking him against his chest, the very picture of a loving older brother. His bloody hand rubbed circles on the back of Satoru’s coat, staining it red. Smirking to himself, he ducked his head to whisper in the boy’s ear. “I know you didn’t mean it, Satoru. You just weren’t thinking, right?”

The boy frantically nodded, burying his face in the fabric of Gaku’s shirt as he cried. “I-I’m sorry, I’m s-sorry—”

“And you won’t do it again,” he said, pulling back and away. Satoru’s face was flushed red, his tears cutting wet streaks across his skin. The sight sent electricity shivering down his skin, and Gaku’s hands gripped at Satoru’s head, forcing them to meet eyes. His fingertips pressed into the boy’s skull, clutching at him like a dying man seeking salvation. “You’re my only friend, Satoru. So I should be your only friend, too. We don’t need anyone else,” he insisted.

Gaku’s face inched closer, his eyes rabidly scanning Satoru’s face. “Okay?”

Satoru stared up at him, his eyes wet and red and oh so desperate for forgiveness. His tiny hands stayed twisted in his coat, as if his precious Gaku-nii was going to get hurt the second he let him go. His tiny chest heaved in panic, hiccups popping out of his mouth. All the while, the tears kept coming, even as his eyes darted across Gaku’s expression—searching for what, Gaku didn’t know.

But it didn’t matter. Not when Satoru, with his quivering lips pressed into a shaky line, nodded.

Real tears surged to Gaku’s eyes, splitting his face into a smile.

It hit him all at once, a wall of—of something Gaku had never felt before. His arms wrapped Satoru into a bone-crushing hug, euphoria and nirvana crashing into him like tidal waves. He knew he knew he knew Satoru would choose him. He always had, from the very first moment they’d met. When the rest of the world would have looked away, Satoru had found him, frozen and buried in the ice and snow.

Even if Satoru couldn’t understand now—he would, one day. When he was older—when the world reared its ugly head, threatening to swallow him whole; when Gaku was the only thing standing between him and cruel reality—then Satoru would know. Even now, Satoru’s arms wrapped softly around his neck, chasing Gaku’s touch—and the smile on his face twisted into something wild.

This was his and his alone.

“Thank you,” Gaku whispered, his talons digging in. “You’re my hero, Satoru.”

Satoru kept sobbing, and in the back of his mind, Gaku realized that this was the happiest moment of his life.

He buried his face into Satoru’s hair, whispering comforts and gratitude, still caging the boy in his grip. Satoru—his only friend, his only everything—continued to shake, every breath whimpered and raw. Gaku could feel his shirt soaking up his tears, the fabric sticking to his skin; could hear Satoru’s soft whispers of his name, rasped into the crook of his neck like a prayer. Gaku reveled in it all, pressing his lips to the crown of Satoru’s head.

This was all he’d ever wanted. And it would be all he’d ever need.

Slowly, steadily, Satoru’s breaths evened out. Gaku waited a few minutes longer, simply counting the boy’s heartbeats against his own, his fingers brushing along the nape of Satoru’s neck. Only when he began to squirm did Gaku finally release him, letting the Satoru retreat back onto the bench. His face was still flushed, drying tears still damp on his face. His eyes were downcast, staring at his own feet, hanging limp between them.

Gaku felt his heart clench a little at the sight. He looked down as well, and saw what was left of Satoru’s reward: the bowl upturned and forgotten, soft serve steadily melting onto the sidewalk. Gaku beamed, immediately leaning in and tilting Satoru’s chin up with a finger. “How about I go get you some more ice cream? How does that sound?”

Satoru blinked at him for a second, as if he hadn’t quite processed the words—before he offered a tired, wobbling smile. “O-okay,” he whispered.

“I’ll be right back then,” he promised, tucking a bit of Satoru’s hair behind his ear. Gaku pushed himself to his feet, rushing back over to the ice cream stand, already fumbling with his wallet. He would show Satoru: he could be his friend, his older brother—anything and everything Satoru wanted him to be. He could make him happy.

And maybe once they were both grown up, they could make this a town where neither of them had ever been: the two of them disappearing to some far-off place, until his brother parents the pain Ishikari was only a distant memory.

Gaku spared one last glance over his shoulder.

Satoru sat still on the bench, staring down at his ruined dessert. Alone.

Everything was as it should be.



Over his second ice cream, Gaku managed to coax more promises out of Satoru’s throat.

Namely, that he wouldn’t tell Sachiko about their little conversation. It was easy enough to do: Satoru didn’t want to upset his mother, now, did he? He was all grown up now, going to school on his own—he was allowed to have a secret or two. Besides, it was fun to have secrets with your friends, wasn’t it?

Or so Gaku had said, a grin stretching across his face.

In the end, Satoru didn’t end up saying anything at all. Exhausted from it all, he passed out the instant Gaku scooped him into his arms. Out of habit, Gaku’s feet carried him back towards their field, both of their backpacks slung over his shoulders. The sun was already low when he spied Sachiko’s workplace, so he stood on the concrete landing, silently watching the silhouettes get longer at his feet.

Which is how Sachiko found them: Gaku waiting on her office’s doorstep, her son sleeping and shivering slightly in his arms.

The awning cut a shadow across the Gaku’s eyes, and he stared out from the dark, a sharp smile slashed across his mouth. “Good evening, Sachiko-san.”

She blinked at him, before slowly smiling back, gently tugging the door closed behind her. “Nice to see you again so soon,” she greeted, her eyes immediately dropping to Satoru. Crouching down, she balanced herself on her heels as she stared fondly at him. “Someone had a big day, I take it. How did it go?”

“Great,” he answered honestly, but his fingers curled tight into Satoru’s clothes. “He drew a cat. We celebrated with ice cream.”

“I see,” she whispered, her eyes softening. Sachiko opened her arms invitingly, and Gaku’s entire body tensed. Every instinct was screaming against it, pulling on logic’s leash—but Gaku forced himself to dutifully deposit Satoru into his mother’s arms. He bit at the inside of his cheek, the boy’s warmth already fleeing his frozen skin.

“Thank you for watching him,” she said, tucking her son against her chest. “It’s a relief knowing he’s out here with you, Gaku-kun.”

Contradiction. Gaku’s eyes narrowed slightly, and he tilted his head, as if seeing Sachiko Fujinuma for the first time. On one hand, she wanted Satoru to make new friends—and those words stabbed into him like a knife, twisting into his flesh. If Sachiko had her way, then Satoru would eventually fall away from him. Not immediately, not completely—but bit by bit, like a satellite slipping out of orbit. Untethered and alone, freefalling through the infinite.

And Sachiko wanted that. She wanted Satoru to leave him behind.

But, she had also invited Gaku in. Sachiko had taught him how to handle a knife, whispering recipes into his ear. He always appreciated the nights the two of them had worked silently in the kitchen, the rice cooker steaming at their side. If nothing else, he was still grateful; still savoured the weeks he got to spend in her home, falling asleep with Satoru curled against his side.

At the very least, they both wanted the same thing: to keep Satoru safe.

And until Gaku was big enough to do that alone, Sachiko Fujinuma was necessary.

Burying the betrayal in his bones, he shrugged Satoru’s bag off of his shoulder, holding it out to her. “It was my pleasure, Sachiko-san.”

She awkwardly nudged the backpack up onto her back, the strap tangling with her purse. “Oh,” she muttered, twisting until her own bag was facing him, both her hands still full cradling her son. She nodded her chin towards the purse, a suspiciously eager smile on her face. “Before I forget—would you mind opening that up for me?”

Gaku stared at her for a second, before he looked down at her bag. His stiff fingers fumbled with zipper, awkwardly tugging; eventually, it came open, and Gaku couldn’t resist peering in. The contents of Sachiko’s purse were very different from his mother’s own: the make-up and disinfecting wipes traded in for bus tickets, hair ties and a wallet stuffed with small bills.

“It’s in the envelope,” Sachiko said. “Go ahead. Open it.”

The paper envelope was squeezed against the back, and Gaku carefully pulled it out with both hands. It was… light, and he looked up at her, one eyebrow raised. She continued to smile down at him, so he bit back a sigh and carefully slipped his fingers under the flap. A glossy finish brushed against his fingertips, and Gaku pulled its contents out.

The memory of that morning was still fresh—but Gaku didn’t recognize the person in the picture.

The Gaku in the photo might as well have been a stranger. His face was… warm, glowing with something gentle and genuine, the corners of his mouth curled in a smile. There was a softness in his eyes that Gaku had never found in the mirror; a happy contentment he’d never bothered to imagine. For a moment, he was stunned, staring down at the person that apparently wore his skin.

Then, his eyes trailed down. Satoru was clumsily holding hands with the Gaku in the picture, happily clutching at few of his fingers. Everything about him was vivid and bright, his cheeks dusted with eager pink. His smile was comically wide, as if he was trying to show off as many teeth as possible. Satoru’s colours practically leapt out of the picture, a stark contrast to Gaku’s gloomy black.

But they held on to each other all the same.

Gaku breathed past the tightness in his throat, blinked the mist out of his eyes, and looked back up at Sachiko. “Thank you.”

She just smiled, before finally standing, Satoru still cradled in her arms. “Hold on to that,” she said, winking. “We’ll need something to compare to, next year.”

Gaku’s grip tightened on the picture, warmth swelling in his chest. “Next year.”



That night, trapped at his parents’ table, Gaku met his father’s eyes.

There was something lurking behind his father’s glasses, dark and ticking like a time bomb. With a deliberate slowness, he set down his polished cutlery, threading his rough hands in front of his plate. Gaku could hear the moment his mother’s breath caught in her throat, her entire body going stock still.

“How was your day, Gaku?”

Gaku nibbled on his meal, staring him down.

He thought about the key to the apartment, hidden in his nightstand. Thought about the picture that he could feel, even now, resting in his pocket—the paper pressed stiff against his ribs, bending with every breath. Thought about the promise Satoru had made, the sound of his sobs like a sweet song in his ears.

He considered all of these things for a moment, and then his mouth stretched wide, all fangs as he grinned. “Fantastic.”