Chapter Text
If one were to look up the precise definition of ‘structural failure’ in the Oxford English Dictionary, they would not find a schematic diagram of a collapsed suspension bridge or a stress-fracture analysis of a load-bearing steel beam. Instead, they would find a high-resolution, brutally honest photograph of Y/N’s living room on a Tuesday afternoon in late August.
It was a scene of absolute domestic devastation. The laminate flooring, which Y/N usually scrubbed to a neurotic, mirror-like shine every Sunday morning, was now a graveyard of packing tape, discarded bubble wrap, and three empty cardboard boxes that sat like grim tombstones in the harsh afternoon sun. A dust bunny the size of a tumbleweed drifted lazily across the floorboards, carried by the draft from the window, openly mocking her.
And there, taped to the glass, facing out toward the indifferent, heat-shimmering street, was the ‘For Rent’ sign.
Y/N had stared at that sign for so long that the bold red block letters had burned a permanent, ghost-like afterimage into her retinas. Every time she blinked, she saw FOR RENT pulsing in the darkness behind her eyelids.
She was a third-year university student, a status that supposedly implied a certain level of stability, direction, and adult capability. In reality, Y/N was structurally composed of 60% caffeine, 30% high-functioning anxiety, and 10% sodium from discount instant beef noodles. Her life was a delicate, carefully calibrated ecosystem of budget management, time optimization, and academic rigor in the Engineering department.
And that ecosystem had just been nuked from orbit.
"We’re really, really sorry, Y/N," Emi had said three days ago, clutching a potted succulent to her chest like it was a holy relic that generated a force field against guilt. "But the rent hike is just too much. It’s criminal, honestly. Plus, Reina wants to move in with her boyfriend, and I... well, my mom thinks I should move back home to commute. Save money, you know? The economy is terrible."
"Right," Y/N had said, her voice sounding tinny and far away, like she was speaking through a soup can on a string. "Saving money. Smart. Very pragmatic."
She hadn't screamed. She hadn't pointed out that they had signed a blood pact (verbally, at least, over cheap tequila shots freshman year) to stick together until graduation. She hadn't mentioned that finding a new place two weeks before the semester began was statistically impossible. She had simply nodded, watched them pack their lives into their parents' oversized SUVs, and then closed the door.
So there she was. The Last Woman Standing. The Captain of the Titanic, watching the lifeboats row away while the freezing Atlantic water lapped at her ankles.
Y/N sat on the floor, pulling her knees to her chest, resting her chin on her kneecaps. She did the math. She always did the math; it was a defense mechanism, a way to impose order on chaos. To keep this apartment—a mediocre two-bedroom unit with a leaky faucet and a landlord who smelled perpetually of mothballs and despair—she needed to find new roommates. Specifically, she needed three strangers to fill the void and the rent check within seventy-two hours.
The past three days had been a descent into a specific, specialized circle of hell reserved for student housing hunting.
She had interviewed a girl named Akari who walked in, sniffed the air like a bloodhound, and asked if Y/N’s aura was purple or chartreuse.
"I don't know," Y/N had replied, gripping her clipboard so hard her knuckles turned white. "I’m an Engineering major. My aura is mostly stress, graphite, and sleep deprivation."
"I can't live with chartreuse auras," Akari had declared solemnly, adjusting her crystal necklace. "It clashes with my root chakra. It disrupts my flow."
Then there was the trumpet player.
"I practice at 3:00 AM," he had said, looking Y/N dead in the eye with no hint of irony, clutching a battered brass case. "That’s when the muse speaks to me. The city sleeps, but the brass sings. It’s spiritual."
"The neighbors will call the police," Y/N countered, rubbing her temple. "We have thin walls."
"The police are just critics with badges," he scoffed, waving a hand dismissively. "They don't understand the jazz."
By the time the third candidate—a guy who asked if he could pay rent in a new cryptocurrency he invented called ‘BroCoin’ and ‘good vibes’—left the apartment, Y/N knew she was doomed.
The silence of the apartment was heavy now. It pressed against her ears, a physical weight. The semester started in four days. Her textbooks alone cost more than her food budget for the month. She was staring down the barrel of homelessness, or worse: moving back into the campus dorms with a randomly assigned freshman roommate who might clip their toenails in bed or microwave fish at midnight.
She rested her forehead against her knees, breathing in the smell of dust, old cardboard, and failure. The panic was a cold knot in her stomach, tightening with every passing second like a winding winch. She was a planner. She had spreadsheets for her grocery list. She had a color-coded calendar. She did not do spontaneity, and she certainly did not do homelessness.
Then, the phone buzzed against the hardwood floor.
The vibration sounded like a chainsaw in the quiet room. Y/N flinched, reaching for it, her hand trembling slightly. The screen lit up with a name that usually promised chaos, high maintenance, and aggressive perfectionism, but today, might offer salvation.
Incoming Call: Kikoru (The Princess)
Y/N swiped answer and put the phone to her ear, bracing herself. "Hello?"
"Y/N!"
Kikoru didn't talk; she broadcasted. Her voice came through the speaker with the force of a glitter cannon, demanding immediate attention. "I heard the tragic news! Emi and Reina abandoned ship! You’re destitute! You’re homeless! You’re practically living in a box under the bridge, fighting raccoons for apple cores!"
Y/N rubbed her temple, a headache blooming behind her eyes. Kikoru had a way of making everything sound like a shonen anime opening. "I’m not under a bridge yet, Kikoru. But I am looking at a very bleak future involving a trumpet player and potential eviction."
"Cancel the trumpet player!" Kikoru chirped, the authority in her voice absolute. "I have the solution. The universe has provided! We have a vacancy! Actually, we have a crisis, and you are the solution to my crisis, which is far more important."
Y/N hesitated. She hesitated hard.
She loved Kikoru. They are cousins. Kikoru was a prodigy, the daughter of the university’s biggest donor, and possessed an ego that was visible from space. But she was also surprisingly loyal. However, Kikoru lived in a different tax bracket. Not literally—they were both students—but Kikoru lived like she was the heir to a small empire. Kikoru didn't buy coffee; she purchased experiences. Kikoru didn't sweat; she glistened.
"Kikoru," Y/N said, her voice guarded. "I can't. Your place is... intense."
"It's not intense! It's cozy! It’s efficient!"
"It's a mansion, Kikoru. You call it 'The Base.' Normal students live in 'units' or 'basements.' You live in a place that has a security system and a name." Y/N sighed, picking at a loose thread on her jeans. "Plus, it’s in Green Heights. That is outside the campus zone. It’s a thirty-minute walk to the Engineering building. Thirty. Minutes. Do you know how much sweating happens in thirty minutes? In September?"
"Think of the cardio! Your calves will look amazing," Kikoru countered, undeterred. "Plus, listen to me—the rent is split five ways. Reno did the math. It’s actually fifty bucks cheaper than what you’re paying for that moldy box you’re in now. And we have central air."
Y/N paused. Fifty dollars cheaper. That was fifty dollars of groceries. That was two textbooks (used). That was a lot of instant noodles. And... central air.
"Who are the five?" Y/N asked, though she already suspected the answer.
"Me, obviously. Reno, obviously," Kikoru ticked them off. "And Reno’s two friends. That’s four. You make five."
"Reno's friends," Y/N repeated, the dread pooling in her stomach again.
She liked Reno Ichikawa. Reno was Kikoru’s boyfriend (or handler, depending on the day), a serious, cool-headed guy who was essentially the only reason Kikoru hadn't accidentally burned down the university with her intensity. He was nice, loyal, played the straight man to everyone's jokes, and was generally harmless.
But Reno’s friends? That was a terrifying variable. Reno hung out with a weird crowd.
"Yes, his friends," Kikoru said breezily, though Y/N detected a slight hesitation. "They’re... fine. They’re house-trained. Mostly. Look, Y/N, do you want to live with Trumpet Guy, or do you want to live in a house with a dishwasher, a backyard, a high-end espresso machine, and me?"
Y/N closed her eyes. She pictured the dishwasher. She pictured not washing forks in the bathtub because the kitchen sink was clogged again with unidentifiable sludge.
But there were catches. Living with Kikoru always came with catches.
Catch #1: The Shinomiya Tax.
Living with Kikoru meant you didn't just eat; you dined. You didn't just grab a coffee; you went to boutique cafés where the barista wore a bowtie, judged your shoes, and served lattes that cost six dollars. The social pressure to spend money around Kikoru was like a gravitational pull. Y/N’s wallet was already weeping at the thought.
Catch #2: The Trek.
Green Heights was a beautiful subdivision. It was also geographically isolated from civilization. If she missed the bus, that thirty-minute power walk would be her daily penance.
Catch #3: The Gender Blender.
"It's mixed, Y/N," Kikoru had warned. Living with three men and one other woman. Y/N had grown up with a sister. She was used to hair ties on the floor and shared conditioner. She was not used to... whatever it was men did. Leaving toilet seats up? Turning the living room into a wrestling ring? Drinking milk directly from the carton like barbarians?
"Y/N?" Kikoru’s voice was softer now, shedding the 'Princess' persona for a second. "Please? I’d rather live with you than some stranger Reno finds on the university forums. I don't want a serial killer in the house unless it's you. I trust you."
Y/N let out a long, defeated sigh. She looked around her empty, dusty living room. She looked at the "For Rent" sign, which seemed to mock her with its cheerfulness.
"Fine," Y/N whispered. "I’ll do it. But I’m bringing my own ramen, and I am absolutely not chipping in for communal scented candles, Kikoru. I draw the line at Jo Malone. And if any of the guys touch my graphing calculator, I will end them."
"Yay!" Kikoru screamed, loud enough to distort the speaker and likely shatter glass in the vicinity. "Pack your bags! Welcome to the good life, babe! I’ll text you the gate code!"
She hung up before Y/N could retract the offer.
Y/N lowered the phone, staring at the blank screen. She stared at the wall. "The good life," she muttered. "Or the beginning of the end."
***
The following Saturday was sweltering. It was the kind of heat that didn't just sit on you; it aggressively hugged you, soaked into your pores, and demanded you acknowledge its presence. The air was thick enough to chew.
Y/N dragged her life’s possessions up the driveway of the Green Heights house, sweating through her t-shirt. Her car, a beat-up sedan named Gabi that sounded like a dying lawnmower and had a check engine light that had been on since the Bush administration, was parked on the street. The driveway was already occupied by a sensible, sleek black Jeep (Reno’s) and a terrifyingly expensive red convertible that screamed Shinomiya.
She stopped at the bottom of the porch steps to wipe her forehead with the back of her hand.
She had to admit, Kikoru wasn't lying. It wasn't just a house; it was a statement. It was a beautiful, two-story structure with pristine white siding and black shutters. The lawn looked manicured with nail scissors, green and lush despite the heatwave. There were flower beds with actual flowers in them, not just dead weeds. It looked like a house where people drank sparkling water, owned ironing boards, and discussed stock portfolios over brunch.
It looked intimidatingly adult.
"You're here! Finally!"
The front door burst open. Kikoru stood there, framed by the entryway like a hostess on a high-stakes game show. It was 2:00 PM on a moving day, and Kikoru was wearing a silk floral kimono that probably cost more than Y/N’s tuition, holding a glass of iced tea with a perfectly spherical ice cube. Her twin-tails were immaculate. She looked cool, collected, and expensive.
"I'm here," Y/N panted, hoisting a heavy box of textbooks labeled FLUID DYNAMICS - DO NOT DROP. "And I think I’m melting. If I dissolve into a puddle, just mop me up and pour me into a jar. Label it 'Y/N' so my parents know."
"Drama queen," Kikoru grinned, tossing her hair over her shoulder and stepping aside. "The room is upstairs. It faces the garden. Feng Shui approved! I saged it this morning to clear out the bad vibes from the previous tenant."
"Who was the previous tenant?" Y/N asked, trudging up the steps.
"Reno’s acoustic guitar collection," Kikoru said. "Very heavy, melancholy energy. Lots of sad indie songs."
Y/N hauled her bags inside. As soon as she crossed the threshold, the temperature dropped fifteen degrees. Central air conditioning. The Holy Grail. It felt like being kissed by a snowman.
Y/N dropped the box with a thud and looked around. The living room was massive. The floors were hardwood, polished to a mirror shine. There was a 65-inch flat-screen TV mounted on the wall, a sectional couch that looked like a gray cloud, and a glass coffee table that terrified her clumsy soul.
But underneath the visual aesthetic, there was a sensory reality. The air smelled of Kikoru’s lavender diffuser, yes, but there was an undercurrent of something else. Something distinct.
It smelled like... boys.
It wasn't a bad smell. It was a mix of Old Spice, faint pizza grease, fresh laundry, and something earthy, maybe sweat or muscle rub. It was the scent of co-ed living.
"Where are they?" Y/N asked, keeping her voice low. "The roommates. The men. The unknown variables."
"Reno is in the kitchen making protein smoothies or something equally healthy. The other two are in the gaming den," Kikoru waved a manicured hand toward a closed door down the hall. Muffled shouting and the sounds of digital explosions could be heard from behind it. "Ignore them. They’re in their natural habitat. Come, let me show you your sanctuary."
They went upstairs. Y/N’s room was, admittedly, perfect. It was smaller than her old one, but it was clean. The walls were a soft cream color. The window actually opened without threatening to shatter.
"I can work with this," Y/N murmured, setting down her backpack. She felt a vague sense of dread uncoil in her chest, only to be replaced by a different kind of anxiety: social performance.
She spent the next three hours unpacking. She organized her desk: pens in the cup, textbooks aligned by height, laptop charger velcro-tied. She hung her clothes, hiding her ratty sweatpants in the back of the drawer and putting her most presentable clothes at the front.
If she was going to live with three guys, she couldn't look like a swamp creature. She needed to project an image of ‘Cool, Low-Maintenance Roommate.’
At 6:00 PM, a voice echoed up the stairs.
"Food!" Kikoru yelled. "We’re ordering Thai! It’s on me for your welcome dinner! Get your ass down here!"
"Free food," Y/N whispered to her empty room. "Okay. You can do this. Savings secure. Socialize, eat, retreat. Don't be weird."
She smoothed out her oversized t-shirt—which featured a diagram of the solar system—and checked her hair in the mirror. It was frizzy from the humidity, but there was nothing to be done about it. She took a deep breath, put on her aloof but friendly face, and walked out of the room.
The walk down the stairs felt like walking the plank. Y/N could hear voices—deep, booming male voices—bouncing off the walls of the open-concept first floor. She rounded the corner into the kitchen.
It was a nice kitchen. Granite countertops, stainless steel appliances, and a kitchen island big enough to land a plane on. Reno Ichikawa was standing there, setting out paper plates with precise, military movements. He looked effortless in a plain white tee and grey sweatpants, his silver-ish hair neatly swept back.
"Hey! There she is!" Reno beamed, looking up. He offered a polite, somewhat relieved smile. "Welcome to the Madhouse, Y/N."
"Thanks, Reno," Y/N smiled, feeling her shoulders relax slightly. Reno was safe territory. "Place looks great. Thanks for letting me crash the party."
"Are you kidding? We needed the sanity balance," Reno laughed, though his eyes held a glimmer of genuine desperation. "If it were just us guys and Kikoru, the power dynamics would be... volatile. We’d be eating off frisbees by next week."
He turned toward the living room archway.
"Oi! Kafka! Hoshina!" Reno yelled, his voice cracking slightly with the effort to be authoritative. "Food's here! Pause the game! Come meet the new victim!"
"Victim?" Y/N raised an eyebrow.
"Figure of speech," Reno winked, placing a carton of Pad Thai on the counter. "Mostly."
There was a groan from the other room, followed by the sound of heavy, stomping footsteps. Two figures emerged from the hallway, bringing a wave of chaotic energy with them.
The first one was burly, older than the rest of them, with a scruffy beard and hair that looked like he’d styled it with a balloon. He was wearing a faded t-shirt that said MONSTER SWEEPER INC. that was a size too small, stretching over his broad chest. He was laughing at something on his phone, not even looking up as he walked into the kitchen.
"Bro, I’m telling you, the sniper rifle is broken, the hitbox is trash—I shot him in the head! The game is rigged against me!" He stopped. He looked up.
He froze. Y/N froze.
It was Kafka Hibino.
Kafka "The Keg" Hibino. The guy who had been a super-senior when she was a freshman. The guy known for failing the entrance exams to the Defense Science program multiple times but refusing to quit. The guy who was loud, obnoxious, and lacked an internal monologue.
"No. Way," Kafka said, his jaw actually dropping. A slow, mischievous, goofy grin spread across his face, crinkling the corners of his eyes. "Y/N? Y/N from the Bio-Chemistry lecture? The one who let me copy her notes that one time I slept through the midterm review?"
"Kafka?" Y/N blinked, her brain misfiring. "You... you live here? I thought you graduated. Or... something."
"I reside here!" Kafka corrected, spreading his arms wide as if presenting a masterpiece. "I bring the flavor! I bring the experience! I am the spice of the Villa! And I am currently a recurring audit student. It's a long story."
Y/N let out a breath she didn't know she was holding. "Okay. Wow. Small world."
She could handle Kafka. Kafka was like a Golden Retriever puppy that chewed your shoes—annoying, loud, prone to making messes, but ultimately you couldn't hate him because he had a good heart.
"And..." Kafka stepped aside, gesturing theatrically behind him. "You remember the Prince of Sadism, right? The man, the myth, the guy who just cheated to beat me in FIFA?"
The second figure stepped out from the shadow of the hallway and into the bright, clinical light of the kitchen. Y/N’s breath caught in her throat. The world tilted on its axis.
He was shorter than Kafka, lean and wiry like a whipcord. He was wearing a simple, dark purple hoodie with the sleeves pushed up to his elbows, revealing forearms that were defined by taut, functional muscle. He wore black sweatpants that hung low on his hips. He had large noise-canceling headphones resting around his neck.
He was looking down at a controller in his hand, a slight frown on his face. "I didn't cheat, old man. It’s called strategy. ‘Ya run in a straight line; I’m gonna exploit it. Ain't rocket science."
His voice. It was distinct. A lilting, melodic drawl that sounded lazy and sharp all at once. It vibrated in the air like a plucked violin string. It wasn't the standard campus accent; it was regional, relaxed, and utterly disarming.
"Hoshina," Kafka poked him. "Look alive. New roomy."
The guy looked up. Y/N felt her heart do a stupid, traitorous little somersault in her chest. A full gymnastic routine with a dismount.
It was him. Soshiro Hoshina.
The Vice-President of the Kendo Club. The guy she had sat two rows behind in Freshman Physics. The guy she had partnered with for a fluids lab once and had been unable to form a coherent sentence around for two hours because he kept smiling at her with his eyes closed.
The guy she had a tiny crush on.
And by tiny, she meant she had once memorized his class schedule so she could ‘accidentally’ bump into him by the library vending machines. She meant she had doodled his name in the margin of her notebook in invisible ink because she was a rational woman of science who was also a pathetic romantic.
She hadn't seen him in a year. He had... upgraded.
If he was cute in Freshman year, he was devastating now. He had a fox-like quality to him—sleek, dangerous, and impossibly relaxed. His dark hair fell over his forehead in a messy, effortless sweep, the undercut visible on the sides. He looked at her. His eyes were narrowed, almost closed, in that habitual expression of his that made him look like he was perpetually amused by a joke only he understood.
For a second, there was silence. Just the hum of the refrigerator and the sound of Y/N’s blood rushing in her ears. Then, his eyes opened. Just a fraction. Sharp, reddish-brown irises locked onto hers.
A slow, lazy smile spread across Hoshina’s face. It wasn't a polite smile. It was a smirk. A knowing, playful, predatory smirk that hit Y/N right in the solar plexus.
He leaned against the doorframe, crossing his arms over his chest, the controller dangling from one finger. He looked her up and down—not in a creepy way, but in a precise, analytical way, like he was dissecting a tactical problem. He took in her frizzy hair, her flushed face, and the solar system t-shirt.
"Well, well," Hoshina drawled, his voice thick with that teasing lilt. "If it ain't the girl who almost blew up the hydraulics lab last year."
Y/N’s face went hot, turning a shade of red that rivaled the ‘For Rent’ sign. "That was a faulty valve! The pressure regulator was calibrated wrong! It wasn't my fault!"
"Sure," Hoshina teased, pushing off the doorframe and walking towards her. He moved with a loose-limbed grace, silent and fluid, like a cat stalking a bird. He stopped two feet away, invading her personal space just enough to make her pulse spike. He smelled like expensive coffee, polished steel, and something clean, like rain.
"I seem to recall ‘ya screaming, though," Hoshina said softly, tilting his head. "High pitched. Like a tea kettle. Real distinct."
"I was alerting the class to the danger!" Y/N defended, her voice sounding breathless to her own ears. She gripped the strap of her bag like a lifeline. "It was a safety protocol!"
"It was adorable," Hoshina corrected, his smirk widening to show a hint of teeth.
He held out a hand. His fingers were long; his palm calloused from sword practice.
"Welcome home, Y/N," he said, his voice dropping to a murmur that felt intimate, secretive. "Try not to blow anything up while ‘yer here, yeah? We’re kinda fond of our security deposit. And Kikoru’ll skin ‘ya alive if ‘ya scratch the floors."
Y/N stared at his hand. Then she looked up at his face. He was looking at her like she was a puzzle he had already solved and found amusing. She took his hand. It was warm. His grip was firm, electric.
"No promises," she squeaked.
Hoshina laughed—a low, genuine sound that rumbled in his chest. He didn't let go of her hand right away. He held it for a tad beat too long, his thumb brushing over her knuckles.
"This," Kafka announced, grabbing a slice of pizza and obliterating the moment with the subtlety of a kaiju attack, "is going to be a disaster! I love it! Who wants extra spicy sauce?"
Y/N looked at Hoshina, who was still grinning at her with that dangerous glint in his eyes, and then at the luxury kitchen, and finally at Kikoru, who was watching the scene with narrowed, calculating eyes and sipping her tea.
Oh no, Y/N thought, panic mixing with a thrill she couldn't suppress. I am in so much trouble.