Chapter Text
Valentine’s Morning
Valentine’s Day arrived softly, as though it were aware of the fragile hope it carried in its palms.
The school had been transformed overnight by the craft club’s tireless enthusiasm. Paper chains in shades of red, blush pink, and snowy white looped across the ceilings of the main hallways, draping from locker row to locker row like garlands in some brightly colored festival. Balloons bobbed gently in the currents of warm air from the heating vents, their ribbons brushing against fluorescent lights with quiet taps. Handmade hearts—some precise and symmetrical, others lopsided but earnest—were taped to classroom doors. Glitter clung stubbornly to tile floors and caught the morning light in soft, scattered flashes.
The scent of sugar cookies wafted faintly from the cafeteria, mingling with the familiar smell of floor cleaner and pencil shavings. Laughter bounced off the lockers as students filtered in, cheeks flushed from the cold February air and voices brimming with conspiratorial excitement. There were bouquets clutched behind backs, gift bags held carefully at one’s side, and whispered strategies exchanged near stairwells.
Amid all of it walked (Y/N).
Her heart sweater—soft cream knit with small red hearts stitched across the front—sat comfortably against her frame, sleeves pushed slightly past her wrists. She had paired it with her favorite jeans, worn in at the knees and perfectly fitted from years of reliable use. On her feet were her pink sneakers—the ones she and Senku had dyed together in his garage during autumn, carefully mixing pigment until it reached the exact shade she wanted.
She knew he didn't care about fashion. That he had probably had other experiments to work on. But they had been hanging out the previous day; where she had been complaining about not being able to find the right shade of shoes. When he stopped and looked at her with that glint in his eyes that said he had an idea.
He texted her the next day asking her to come over. And when she got to his place, she found him setting up the tarps and bins.
She remembered how focused he had been that afternoon.
“Precision matters,” he’d said, crouched beside her with gloved hands and a measuring beaker. “Even when it’s just shoes.”
She had teased him for calling her shoes an experiment, but he’d only smirked in that infuriatingly confident way of his and replied, “Everything’s an experiment.”
Now the sneakers squeaked faintly against the polished hallway tiles as she walked, and the memory warmed her from the inside.
She hugged her binder to her chest, weaving through clusters of classmates. Every few steps, she caught glimpses of red envelopes or heart-shaped boxes being exchanged. Some faces were shy, others triumphant. A few were already flushed with embarrassment.
Her gaze drifted, almost instinctively, toward the far end of the hall.
Toward his locker.
The Question
Senku Ishigami stood out in any crowd without even trying. His gravity-defying hair made certain of that. Even from a distance, she could see the unmistakable pale green tips rising like the flick of a flame. He was standing near the science wing entrance, one shoulder propped against the wall as he scribbled something into the small notebook that he always carried on him.
He didn’t look up once.
Of course he didn’t.
While the rest of the school buzzed with romantic anticipation, Senku appeared as he always did—entirely consumed by whatever problem currently occupied his mind. A pencil rested behind his ear. His brows were drawn together in sharp concentration. A faint smudge of graphite streaked across his knuckle.
(Y/N)’s stomach fluttered.
She slowed her steps.
Should she interrupt him?
The thought had been circling her mind since the night before. She had rehearsed at least four different opening lines in front of her bedroom mirror.
'Hey, Senku, do you want to come over tonight?'
'Are you busy after school?'
'I was thinking we could—'
Each version felt clumsy once spoken aloud. Too abrupt. Too vague. Too revealing.
She had never been afraid to talk to him before. They’d spent hours together over the years—studying, experimenting, debating theories that went far over her head but that she enjoyed listening to anyway. She knew the cadence of his voice when he was explaining something. She knew the tilt of his mouth when he was amused but pretending not to be.
But this felt different.
Today wasn’t just another afternoon in the lab.
It was Valentine’s Day.
She watched him flip a page, mutter a soft “That’s it,” under his breath, and push himself upright. A couple of students approached him hesitantly with small bags of candy. But he walked off before they could get his attention. His expression unchanged as he made his way down the hallway. In the opposite direction of her.
He wasn’t cold.
He was simply Senku.
Logic first. Everything else… somewhere after that.
(Y/N) chewed lightly on her bottom lip.
If she interrupted him now, she would derail whatever thought process he was currently riding. She could see it in the intensity of his posture—that electric hum that surrounded him when he was on the edge of solving something. The way he walked with a single focus through the crowd of students.
She didn’t want to be the reason that spark dimmed.
And yet…
She wanted to ask him.
The idea of the two of them spending the evening together had been quietly blooming in her mind for days. Cooking something simple. Laughing over mistakes. Watching his eyes light up the way they did when an idea took shape.
Her fingers tightened around her binder.
She could wait until lunch.
No. By then, the hallway would be chaos.
After school?
What if he left immediately for the lab?
She exhaled slowly.
There had to be another way.
Ink and Intention
By the time first period ended, she had made her decision.
If she couldn’t say it without stumbling over her words, she would write it.
The library during passing period was blissfully quieter than the hallways. Sunlight filtered through tall windows, casting pale rectangles across wooden tables. A few students sat scattered between shelves, heads bowed over textbooks.
(Y/N) slid into a chair near the back, pulling a sheet of pastel stationery from her binder. She had chosen it carefully the night before—a soft cream color with a faint border of tiny red hearts. Just in case she couldn't work up the courage to ask him directly.
The paper wasn’t overwhelming. She didn't think it was too childish. It was just enough.
She placed it flat on the table and stared at it for a moment.
Then she picked up her pencil. Wanting to write it out before making it permanat with ink.
Her handwriting was neat but slightly rounded, letters curling gently at the ends. She paused after every few words, considering phrasing with care.
'Dear, Senku.'
Too formal.
She erased it off of the paper and tried again.
'Hey, you.'
No. That sounded strange.
She pressed her lips together and smiled faintly.
'Hey, Senku.'
Simple and honest. Just like her confession.
She continued.
'I know you’re probably busy today (because you’re always busy), but I was wondering if you’d like to come over after school?'
She paused, then added:
'We could make dinner together. I was thinking ramen?'
Her smile grew as she drew a small bowl beneath the sentence, steam curling upward in tiny loops. She shaded in the broth carefully, adding a pair of chopsticks resting across the top.
He would appreciate the detail.
'And if you’re working on something new, I’d love to help.'
She drew a small rocket beside that sentence—sleek and pointed, with little bursts of flame at the bottom. It was slightly crooked, but charming.
'Biology and Chemistry team for the win right?'
'Text me your answer?
Her pencil hovered.
Should she add more?
Something sentimental?
Her heart thudded softly against her ribs.
No. If she added too much, it would feel heavy. Pressured.
This was meant to be light.
Hopeful.
She carefully lined over her writing with her favorite pen. Staring at the paper, she signed her name at the bottom with a small flourish, then folded the paper carefully into thirds.
For a moment, she simply held it.
Her pulse felt louder than the quiet murmur of the library.
The Locker
By mid-morning, the hallways had grown even livelier. Paper hearts had begun peeling slightly at the corners from the humidity of so many bodies moving through the space. The air buzzed with anticipation.
Senku’s locker sat in the science wing corridor, slightly removed from the main traffic. It was dented near the bottom from an incident involving a runaway cart sophomore year. A small, faded sticker of a periodic table clung to the inside door.
(Y/N) approached it with cautious steps.
She glanced down the hall.
Empty—for now.
Her hands trembled just slightly as she unfolded the note one last time, smoothing it flat.
She had come prepared.
From the pocket of her jeans, she pulled out the small green flask magnet—a novelty item shaped like an Erlenmeyer flask, filled with glittery faux liquid that shimmered when tilted. She had found it in a science store months ago and bought it on impulse, knowing immediately whose locker it would eventually belong to.
It felt right to use it now.
She opened the locker door gently.
Inside, it was predictably organized chaos. Notebooks stacked with sharp precision. A pair of safety goggles hanging from a hook. A slim container labeled 'Calcium Samples' tucked neatly to one side with Senku's scrawling handwriting written across it.
She smiled.
Carefully, she attached the note to the inside of the locker door, securing it with the green flask magnet so it wouldn’t fall.
Then she reached into her binder again and withdrew the photograph she had been keeping.
It was Senku’s favorite.
What he didn't know though, was that it was her favorite too.
it had been taken at the observatory last summer.
They had snuck up onto the rooftop platform after hours with permission from the astronomy club. Senku had planned the whole thing for them. His excuse was that he wanted to watch for some phenomenon that never happened. But he had asked her to accompany him.
The sky had been impossibly clear that night—an ocean of stars scattered in luminous clusters. The Milky Way had stretched overhead like a river of light.
She remembered the way they sat on the roof together. Him helping her to lay out the blanket she had packed after he told her their plans for the evening.
She loved the way his eyes lit up when talking about the different stars and constellations. The way he smiled, hands moving erratically while he spoke to her. She recalled the way that it felt so different from his usual science spiels. That the more he talked, the calmer he appeared.
They spent the whole evening talking together. Senku answering all of her questions and sharing his wealth of information.
There was something about the stars that just fit Senku. And that's what made it her favorite photo of them.
In the photo, Senku stood beside her with his hands shoved into his pockets, smirking slightly. She stood close enough that their shoulders brushed. The stars behind them made everything feel infinite.
He had said that night, quietly, “Statistically speaking, this is one of the best views we’ll get this year.”
She had replied, “Then I’m glad I’m here with you.”
She remembered the way his gaze had shifted, just for a second.
She slid the photo behind the note so that the edge peeked out beneath it.
There.
Out of the way. But still safe.
She closed the locker gently, her fingers lingering on the cool metal.
Her chest felt tight—but not unpleasantly so.
It felt like standing at the edge of something new.
Between Classes
The rest of the morning passed in a blur of red decorations and whispered confessions.
In math class, someone received a serenade from the choir club. In history, a bouquet of roses was delivered to the wrong desk, resulting in flustered apologies and laughter. Even the teachers seemed softer today.
(Y/N) tried to focus on her notes, but her thoughts kept drifting.
Had he opened his locker yet?
Had he seen it?
What would his expression be?
Would he smile? Smirk? Blink in confusion?
Her fingers hovered over her phone during passing period, resisting the urge to check for a message.
Nothing yet. That was fine.
He might not have needed anything from his locker this morning. Or maybe he had opened it and was simply thinking.
She tried to steady her breathing. Cautious optimism. That was all she allowed herself. She didn’t expect grand gestures. She didn’t need them. She truly was happy with their relationship. And she knew how Senku was. Science was his first love; everything else came second.
She only hoped—
Only hoped that when he saw the note, he would understand what she meant beneath the simplicity of the words.