Author’s Note: Soft Sanemi anyone? I enjoy writing soft sides of baddies because that’s how they areeeee. Anyway, ever since I got to know Sanemi in Kimetsu Academy is a math professor, I knew this was coming. So here it is! Tell me what ya’ll think!
Word count:4412
Pairing: Modern! Sanemi Shinazugawa x Reader
Warnings: fluff, mutual pining, soft nemi
Originally posted by seieiryu
❝
For as long as you can remember, your interactions with Shinazugawa Sanemi have been strange. You weren’t one to abruptly jump and exclaim that it’s meant to be or the mere cinematic aspect of him popping up everywhere would actually amount to something. Nah, Sanemi as a person gave you very little to fantasize about. But, it was true and some close to you were noticing it after years.
Sanemi and you shared a fateful relationship that forced you to enter each other’s lives unexpectedly.
It began with middle school. You never knew Sanemi before middle school, but it was when you joined did you understand that your senpai was someone no one could mess with. He was apparently very kind before—but something had happened that changed him.
You were in your first year of middle school when Sanemi was in his last, and despite not interacting with him at that time, you knew of him. He was brash, would amount to teasing every single person he came in contact with and would pull pranks on other students. Sanemi was a force as a child, and you started to believe that it would never change.
It didn’t.
Strangely, you joined your first choice of high school—again, where Sanemi was your senpai. This time, as luck would have it, he noticed you. He gave you a mean glare—the meaning of which you had no idea about—that caused you to whimper and look away, not wanting to run into him. You didn’t know Sanemi was part of the high school you chose, which had a fairly decent reputation. Considering his brash self, you never pegged him for a well-achieving student.
Your interactions were scarce—your ‘senpai, I’m sorry’ whenever you bumped into him (you were part of the newspaper club, you really loved writing and editing, some teased that you’d become the English teacher someday). Sanemi wouldn’t even utter your name, you didn’t even know if he knew your name to begin with, but would click his tongue and ignore you. You took that as a good sign because he normally yells at people who bump into him.
What caused your fascination with Sanemi-senpai was a small yet brief incident during the school festival. His face, at the time, was scarless, so there was a line of girls who wanted a piece of Shinazugawa meat, not considering the fact that he wasn’t interested. Which was weird, you thought, because he could have any man or woman he so desired. But, that was the thing—he didn’t desire.
Sanemi was criticized during the festival by a faculty member that he wasn’t taking part in the events his classmates were working so hard for. Begrudgingly, he decided to be the cashier for an event—a cat cafe event—and since Sanemi was good at math, he was asked to count and collect the revenue that came in. You and your good friend decided to pop into the cafe just to see what your attractive senpai was doing. You wondered if you were the only one who found him intimidating, whereas the whole population of girls believed his bad attitude was attractive. You wondered if they found him attractive for the wrong reasons.
“Look at him!” Your friend cooed, and you did look at him, only to spot him doing absolutely nothing and staring blankly ahead of him with no emotion.
Clearly, he was bored and didn’t want to be there. You turned to your friend and felt several sweat drops on your forehead at her wasteful enthusiasm. You didn’t understand what she was trying to do, was she trying to impress him?
“I’m going to ask him if he wants to join us for a cup of coffee.”
Your eyes widened. You put your hands forward and shook your head.
“I really don’t think that’s a good idea—”
“Why not? You have your eye on him or something?”
You blushed at the accusation, only wishing for your friend to know that Sanemi isn’t someone who can be impressed so easily. You always believed he’d want something else, a wistful type of want where you desire after something you can’t have—Sanemi had a deep aura embedded underneath all that menacing outwardly appearance, which was clearly not who he was. And here was a girl, your friend, who was completely infatuated with his demeanor.
“N-No, I don’t think he can stop or pause midway—”
“No harm in asking!”
Sometimes, you wished you were as upfront as your friend was. You let out a squeak before praying for your friend. Sanemi would yell at her and it would break her heart and you’d have to do all you could to console her and tell her that it wasn’t her but him. However,
“Would you like to join us for coffee?” Your friend asked with a smile.
Sanemi looked at her with a blank expression, “No,”
He turned and looked at your bewildered expression and for some reason, you felt so sad. There was nothing menacing about him right then, there was absolutely nothing scary. In one moment, all your apprehensions about Sanemi flew away, and there was no way you were ever going to be intimidated by this guy again.
He looked down at the counter and muttered, “If you’ve got nothing to buy, leave.”
Your friend giggled and came back to you, but you stood up this time and approached your senpai. Sanemi grumbled before noticing it was you. You, whose face he remembered since middle school, whose name he kept forgetting, whose only reactions were once whimpers when you saw him, which had gradually changed to softer and hesitant greetings to now this,
“I’m sorry if she was too forward, senpai.”
Sanemi merely looked at you, reactionless.
“It’s fine.”
And that was that. You were impressed, and the blooming of a crush was formed. The more you thought of it, the more it didn’t make sense, and the more it didn’t make sense, the more you liked it.
You’d smile at Sanemi whenever you saw him now, a soft smile reserved just for him, which he’d ignore obviously. You’d often bump into him on the terrace, completing his homework on his own. Your heart went out to him, you knew of his large family and how his father walked away and how he managed two more jobs alongside school to take care of his family.
You wouldn’t say anything, because that would make you friends. Whatever it was that you shared, you enjoyed it.
Wordless, silent, and comfortable.
You felt your heart shatter at the mere thought of him graduating, but you knew he had to go. He was selected in a college in Tokyo, for mathematics, and you knew he was going to excel in it. You wanted to give him something, you wanted to take something from him before he left, but it was strange—you knew there was no possible way you could feel something so strongly for him considering you were a mere 15-year old and he was close to being 18.
But, here you were, tearing up on his graduation day, trying hard not to show how much you grew to like the person he was hiding behind the aggressiveness he normally displayed.
On his graduation day, you rushed over to him—he was again, avoiding people while being on the terrace.
“Shinazugawa-senpai!” Sanemi turned to you with a scowl, which you’d like to believe reduced in intensity upon the mere sight of you, “I… I want to give you something!”
He’d thrown out an entire box of buttons the day before and if you were also giving him a button, he knew he’d lose it. There was no way he was going to—
His eyes widened. You were giving him a pen?
“I know you like pens. I always find that you have a new one every month… Whenever you complete homework. I just… I want you to have it for college—”
“Ridiculous.”
You knew he didn’t mean it and giggled at his expression. He took the pen from you and shoved it in his pockets. You knew he’d give it a good long look when you weren’t there. He was looking at you now, his intense glare directing at you, wordlessly.
“Aren’t you scared of me?”
You shook your head as if you were expecting this question.
“Why? I haven’t been nice to you in my life.”
He was right. He was rude, brash and arrogant. He hadn’t been nice to you.
“But, you haven’t been mean either.” You said, smiling widely.
You heard him scoff before coming forward and ruffling your hair. You felt your stomach flip at the contact, but that was all you could expect now anyway. A second later, you felt him hold your hand, your eyes widening at his action—a gasp exiting your mouth as you felt something cold being placed there.
“It’s a button…” Sanemi was struggling with this, “From my shirt… The second button.”
It was a gold button—big enough as a small pendant for a chain. You already knew what you were going to do with it. You smiled before accepting it, bowing down and wishing him good luck, saying goodbye hurt but this was nice—you were acknowledged, and so were your feelings. Sanemi Shinazugawa was your first love, and that was that.
*
When Sanemi looked at you for the first time, he thought you were an idiot.
It was a fleeting gaze, you see a person as you pass the corridors, never to spot them again or remember their face. Some faces you remember because they were prettier than the rest or uglier than the rest. Some you remember because they had a weird hair color or a big nose. Sanemi remembered your face because it looked like an idiot.
Who smiles like that anyway? Like a dumbass with no care in the world? Oh, so birds like you? How childish. He couldn’t waste his time looking at someone like you. You were three years younger than him, you were practically no one.
When Sanemi looked at you properly for the second time, he was confused. You were once again his junior in high school. It confused him, how you—of all people—you had turned up as his junior in this school. It made no sense. Funnily enough, he didn’t think you were an idiot this time. You were kind of cute but were shyer than before.
You would whimper whenever he scowled at you, which again, he found a tad bit cute but also insulting. He wasn’t a ghoul for you to look so afraid of him. But, something had changed—he couldn’t quite put his finger on it, but things had changed after the school festival.
You voluntarily walked over and spoke to him about your dumbass of a friend hitting on him. He realized that there was no use yelling at girls who found him attractive, because 1) he knew he was attractive, and 2) he really wasn’t interested in them and 3) they approached him more when he yelled at them, and this last point made no sense to him whatsoever.
But, you approaching him made no sense either. In fact, it confused him more. You would greet him whenever you saw him, sending him a soft smile or a wave, whatever was appropriate at the time.
Around this time, when Sanemi looked at you, he thought you could be someone he could talk to. You could sit in silence for hours and he wouldn’t feel uncomfortable. You wouldn’t try to fill the space with awkward conversation or small talk—two things Sanemi hated the most. You were just comfortable with him when he completed homework, and you read a book or did something else he didn’t quite pay attention to.
He paid attention to the fact that he didn’t pay attention to you, which meant he was paying attention to you. When Sanemi understood this, he wanted to be around you more but his graduation was approaching and it was as if reality was letting him know that it was either too late or never going to happen.
However, he had always been a weird sort of fighter. When Sanemi gave you the second button on his shirt, he took a good long look at you. It was the third time he had allowed himself to give you a long, customary Sanemi-look, which took a mental picture of you for him to remember when you were not around.
When Sanemi looked at you, that third time, he knew for a fact that you would one day become his wife.
*
There’s no way… You were bewildered, and it was as if fate wanted you to fail in the subject you hated the most. You were excelling in English and that was what you wanted to study. You didn’t want to study anything else, you were, in fact, very happy that you had your entire life sorted out at the young age of 18. You were going to attend college and get an English degree and you were going to teach.
How good is math in your life? Not very.
How good is math in your life if your first love, senpai from the past, senpai from middle school, was the one teaching you?
You were definitely going to fail.
The aura he brought into class as he was introduced as your new class’s assistant faculty was menacing. You had actually almost forgotten what this feeling was—but as soon as he stepped inside, you were reminded of it brutally, as if the aura had never walked out on you at all. He had scars on his face now, a story you knew you’d probably never know. Sanemi didn’t even look at you, you believed he forgot about you; but you stupidly still wore his button around your neck—people often teasing you about a long lost senpai you were crushing on from the past.
Everyone remembered Sanemi, everyone was scared and no one knew that the button belonged to him. It was a secret you were sure were to take to the grave, but now the chances of that were slim.
“This is why I think fate is modulating your interactions with Shinazugawa-sensei!” Your friend exclaimed.
“It’s nothing like that… I think he just got a job here and it’s paying well—”
“What if he came back for you?”
You rolled your eyes. There was no way he’d have come back for me, you thought, your heart flipping at the mere thought. You watched as Sanemi walked into another classroom, hearing rumors about how he was incredibly strict with his students. That didn’t surprise you at all, and in fact, you liked how serious he was about the subject he liked. A soft smile sat on your lips and you were lost in thought until—
“Thinking about Shinazugawa-sensei?” Your friend teased you before you growled and pushed her away playfully.
Once you were alone, your fingers traced the texture of the button he gave you, which was still around your neck like a small charm. You’ve worn it for two years now—the two years he wasn’t there. It wasn’t as if you never had crushes after that, you did. You even had a relationship in school, the cute and fleeting glances, hand-holding and the first kiss. You had your first heartbreak as well when you caught your then-boyfriend sticking his tongue down your junior’s throat.
In two years, you believed you had moved on from Shinazugawa-senpai, no, -sensei, but turns out, your feelings returned tenfold with him just walking into your class.
“Is there a problem?” Sanemi growled at one of your classmates, who was asked to solve a question on the board.
You gulped and thanked the heavens it wasn’t you. You definitely didn’t know how to solve the question, and you didn’t want his wrath falling down on you. However, you knew of him and you knew him. You knew he just wanted his students to learn. You watched as he loudly explained how to solve the question, and you unconsciously took down notes, actually paying attention.
“Any questions?” He snapped at the class, which was dead quiet.
Your hand went up in the air, bringing down a deathly aura around you. You looked so intrigued, your eyes closed and your hand in the air steady, your lips curved into a soft smile.
“I have a question.”
You were sure your classmates were fully intent on killing you and hiding your body, but since the class time was up, no one had the obligation to wait.
“Get out.” Sanemi told the rest of the class, and you assumed was the rest of the class because you didn’t budge, as the class exited the room, relieved.
“Sensei, my question—”
“What is it?”
You stood up and brought your book over, asking him the question. Calculus was very hard, and you weren’t very good at it. Sanemi took one look at your notes and knew you were struggling, but you were trying. He normally hated it when his students were bad at his subject, but then there was you—you, who were really, really bad, but was also trying very hard.
He explained calmly and you kept asking him to repeat—annoying him, making him yell at you, but you patiently listened, looking bashful. When you finally understood, you thanked him, and bowed, causing the button pendant to slip out from inside your collar and dangle. You hadn’t noticed it was showing, but Sanemi had. His eyes widened just a bit before noticing you walk away, causing him to stare at the pen he was using to explain a math problem to you.
The pen you had given him.
He knew of his shortcomings, but it was rare to find a person who wasn’t appalled with his attitude. He was sure of it, though. He’d looked at you properly for the fourth time and thought the same thing he thought when he looked at you properly for the third time.
*
During your graduation, you missed meeting Shinazugawa-sensei, but luckily for you, he gave you a smirk when the assembly was about to begin. You didn’t know what the smirk meant, but on the rare times you had seen it and your heart flipped, this had managed to do the same once more. You unconsciously touched the button necklace, something Sanemi noticed you do (and he knew what you were doing because he had given you the damn button).
You attended Tokyo University, Sanemi’s alma mater, for English. It was only for a year, luckily for you, and you knew you were going to have to come back home for your family. You’d look for a job there, but what you didn’t know was one of your old faculty members was teaching in Tokyo.
“You should join Kimetsu Academy!” He said, patting your back.
Your heart flipped at the thought of your old school, the school where Sanemi teaches still. He had been your senpai, your sensei, and if you were to join Kimetsu Academy as a TA, he’d be sensei again, but so would you.
Although part of your motivation in joining Kimetsu Academy was teaching in your old school, you couldn’t deny joining Kimetsu for Sanemi. You weren’t sure if he was married now—you were 22 years old, which meant he was 25. You were hyperaware of him and what he was doing and you knew he would be surprised with this move.
On your first day, you took your time walking through empty corridors. You remembered the locker you used back in school, where you’d place your outdoor shoes and your indoor shoes. You let out a sigh as you walked past your old classrooms, feeling warm on the inside.
“How long do you plan on wasting time?”
You jumped and turned around to spot Sanemi, leaning against the opposite wall, looking at you as if you were crazy. Your eyes were wide and you felt like you were going to have a panic attack. Your heart was beating erratically, and your mind was blank. You were not ready to see him yet, you wanted to see him surprised and yet, here he was, surprising you!
“Shinazugawa-senpai…” You voiced, placing a shaky hand against your heart. “You… You scared me—”
“You still wear it?”
You blinked, “Eh?”
Sanemi pointed to his own neck and your eyes widened. Your face reddened and you let out a soft squeak before earning a throaty chuckle from him.
“H-How did you… I mean—I… It symbolizes the essence of my childhood, it’s… it’s not what you—”
“Shut up,” Sanemi said, sighing. “Didn’t really think it’d be goodbye for real, did you?”
You blinked, confused.
“What do you mean?”
He took one good look at you. The fifth time. And when Sanemi smiled at you, you thought you’d actually die.
“Life keeps throwing you back to me. Didn’t think it’d be a fucking coincidence, did you?”
“What did you think it was?”
You weren’t sure why you were so nervous. You weren’t sure why this felt like he was confessing to you. He merely shrugged and walked away, leaving you there with more questions than answers.
A month passed, with bare minimum interactions. You had made new friends, and you were getting better at teaching and handling a noisy classroom. You wore your button necklace with pride, flaunting it almost, sending secret smiles to Sanemi who sent you secret glances in return. Soon, the secret glances were late-evening interactions, when the two of you would stay back to correct answer papers.
It was one particularly long night when you realized you were utterly and irrevocably in love with Shinazugawa Sanemi. You still had four more sheets to go, and the time was over 8 p.m., in the night. Sanemi was still in the staff room as well, correcting his own bunch of papers—cursing here and there about how terrible kids were at math. You’d generally interrupt with a mild conversation, but Sanemi noticed how you hadn’t uttered a word in over an hour. He paused, noticing how he had one more paper to go, and turned and looked at you.
You were engrossed in reading the students’ papers. You had a stern look on your face, the sternest you could conjure, and you were chewing on the back of your pen—a habit Sanemi hated, but found adorable when you did it. He took a good long sixth look at you right then, your hair messy, your eyes having heavy bags underneath them, your fidgety fingers, and he thought the same thing he thought when he saw you for the fourth time and the fifth time.
He was so sure you would become his wife. He was so sure.
But perhaps, the sixth time he looked at you was a bit different. Sanemi felt a strange nostalgia upon seeing you, wearing his button around your neck with pride, remembering how the first time he saw you he thought you looked idiotic even. He hadn’t realized he was watching you for a couple of minutes now, in utter silence, and enjoyed the whole while.
Oh shit, Sanemi’s eyes widened. Oh, fuck.
His mother had warned him about how Shinazugawa men fall in love. They fall rock hard and it would most often kill them. The realization hits them at a young age, they were sure of what they wanted and Sanemi was sure as well.
But for the first time in his life, he was floored.
“Oi,” He let out, a serious expression sitting on his face. “(y/n).”
He had resorted to calling you by your first name, not that you complained.
“Hm?”
You were paying the papers more attention than him. You really were a good teacher.
Sanemi stood up and walked over you, you weren’t even aware that he was approaching you, and stood by your side. He looked at the papers, the long answers and the amount of red pouring into them. He looked at your head and leaned down, his mouth right next to your right ear. You shuddered when you felt a breath on your ear, but you didn’t move.
Slowly, Sanemi pressed his lips to your cheek and stood there, waiting for a response. He didn’t want to scare you—he hated scaring you, but he did enjoy flustering you.
You were frozen like a rock when he pulled away. Sanemi wasn’t one to casually give off affection like that, but there were times you knew he could be gentle. You turned slowly, to meet his gaze, his hand supporting him as he bent down to your level. Your face was bright red, but your eyes were intense.
“Shina—”
“No.”
You gulped. You understood him too well to know what he meant.
“Sanemi-san.”
He grinned before looking at your lips once, twice and then into your eyes before noticing your hands reach up to his cheeks. The sexual tension was palpable in the air, and just as soon as your hands touched his cheeks—he took the plunge. He kissed you, like Sanemi would, rough and passionate—his hands buried themselves into your already messy hair and he kissed you some more. He captured your lips into his own, before pulling out and kissing your jaw, your neck, and your eyes, before plunging and kissing you again.
You gasped when he brought you to a standing position, pulling you closer to him and kissing you harder, but also softer—a compassionate side of Sanemi’s most people were not allowed to see.
When he pulled away, it was as if you would die if you didn’t tell him.
“Sanemi-san, I… I love you.”
He knew. He knew it from the third time he had seen you. He grinned before laughing, confusing you, offending you—but you had seen it.
Your eyes widened a tad bit when you saw the adoration he had in his eyes as he looked at you.
The seventh time Sanemi Shinazugawa saw you, he was floored; he was deeply, and devastatingly in love with you.
And while people relied on words to express their feelings, there you were. You were fluent in Sanemi’s own internal language. You had always been. And it had always, always been you.
“For… For how long have you—”
The question was left hanging in the air for a bit before Sanemi answered how Sanemi would.
“Shut up.”
❞
