Archive of Our Own ^beta

Chapter Text

Senku didn’t need much to live well.

Just a house with a big basement for a personal lab, a good school for his son, and his job at NASA.

Two out of the three were already settled. His son was about to start at a great school on Monday, and there were only a few items left before he could finish his personal lab.

But one thing was missing—the most important one: his job at NASA. Don’t get it wrong, he had a solid sixteen years within the institution, working alongside his close team of friends.

But last month, a fateful personal accident at work left a letter of leave on Senku’s desk, along with advice from his mentor. The letter stated he would be away for eighteen months, to avoid future problems and ensure his mental health. Xeno’s advice, however, was more direct—almost like a suggestion, or perhaps a command.

“Take this time to think. I don’t want my best student lost in the abyss.”

“NASA won’t pay my bills during this so-called vacation, Xeno. I have a child to raise.”

“Then do something simpler, colleague. I know of a job that will keep you busy and still pay for dinner.”

And so, there he was, signing the last paper of his contract at Nanami middle School.

Senku wasn’t exactly a teacher, but the idea of teaching chemistry to preteens felt mildly exciting—in a good way. As he took off his reading glasses, needed now thanks to his slightly advanced age, he noticed movement in the office. He already knew who it was, but waited for the other to make the first move.

“Dad?”

“Hello, Newton.”

The first thing his crimson eyes caught was the white hair with black tips—it reminded him a lot of Byakuya’s. Senku thought his father must have felt the same way when he adopted him. Small hands tried in vain to reach the office desk, and then those blue eyes—so deep they could easily be mistaken for black—pleaded with his father. Senku understood immediately: the boy wanted to climb onto his lap.

“What are you doing?”

“Just signing some papers. I’m heading to bed now.”

“You’re lying!”

That pouty face carried worry too. Newton was only six years old, but he cared deeply about his father’s health. Senku was always fascinated by his son’s ability to understand other people’s feelings at such a young age. He knew there was a reason for it, but he didn’t like to talk about it.

“I swear I’m not. I’m going straight to bed—just three liters of caffeine first.”

“DAD!”

Senku let out a muffled laugh. He really was turning into his own father.

“Since you’re not going to sleep, can you put on some Gen Asagiri show?”

That name. That name irritated him deeply. Newton had only recently become truly aware of the world, but ever since he was two years old, the boy had been fascinated whenever that magician appeared on TV. Asagiri was his very first idol, and Senku was deeply jealous of this idolization.

“Tomorrow you have class, Newton! You can’t stay up late.”

“But Senku.”

The father’s proper name was a trap mechanism taken straight out of Asagiri’s mentalism books, which had been Newton’s fourth birthday gift and the very object that made him learn how to read.

“To bed.”

The disappointment on young Ishigami’s face was clear. On a normal day, Senku would have lost the mind game to na eight-year-old, but a new phase in their lives was about to begin. Not that Senku cared about any sentimental nonsense, but he had a good feeling about the times ahead.

 

Gen Asagiri didn’t need much to live well.

Just a cold Coca-Cola, a good school for his daughter, and his magic/mentalism shows.

He already had two out of the three things on his personal list: his daughter would be starting at Nanami Secondary School on Monday, and his fridge was well stocked with soda.

But there was still na uncertainty in his lifestyle—his celebrity career. Since the age of sixteen, Gen had lived a hectic life as a magician who captivated everyone with his words and gestures.

In the last quarter, however, a heated argument had cost Asagiri much of his credibility in the media, as well as the trust of his agent of fourteen years.

“Want some advice? You know you’re in your last years of success.”

“Delicate as always, Vincent.”

“I’m serious. Take some time away from the spotlight. By then the climate will cool, and I’ll find a way to get you back in the media with notoriety.”

Gen made a mental note. Eighteen months should be enough for the public to forget his reckless fight with that so-called famous celebrity.

He also decided to pull his philosophy degree out of the drawer and distract himself with na activity unusual for his daily routine.

Imagine walking into class and finding a global celebrity at the teacher’s desk teaching philosophy—that’s what the students at Nanami Primary School could expect.

While lost in thought, he heard the click of the TV remote, and his eyes adjusted to the new brightness—or rather, the lack of it. Someone had turned off the television.

In the dim light, it was still possible to see the brown eyes shining almost like rubies, dimmed only by the annoyed face. The snow-white pigtails and the two green front strands swayed toward him as the girl grabbed his arm without delicacy.

“It’s time for bed, Dad.”

“Hoshi? What time is it?”

“Bedtime. Come on, you start work tomorrow, and I have school.”

“Just five more minutes, sweetheart. The program was almost over.”

“You weren’t even watching, Dad. And by the way, watching TV before bed will ruin your sleep quality and suppress your melatonin production.”

Like a walking scientific dictionary, Hoshi listed with precision the harms of late-night television. Gen was far too tired to understand any of it, but he listened attentively anyway—he loved seeing his daughter’s passion for knowledge.

“And why are you still awake?”

“I was doing something productive, Dad. I finished reading and analyzing Dr. Ishigami’s latest paper.”

Senku Ishigami wasn’t a typical idol for a twelve-year-old girl, but he was Hoshi’s. Not that Gen hated the scientist, but his daughter seemed to admire the man she had never even met more than her own father. That made the mentalist feel a twinge of jealousy.

“I forgot you were obsessed with your boyfriend’s new paper.”

“DAD!”

Her blushing face matched her reddish-brown eyes perfectly. The older man couldn’t resist teasing his little girl, but perhaps the tired smile under his eyes wasn’t just amusement—maybe it also hinted at hope for new opportunities.

 

The classroom was full when he arrived. Curious eyes, hormones raging from having to wake up so early.

His own tired eyes were indifferent—he had already faced tables full of genocidal politicians and psychopathic elites. He could handle this.

“Good morning, class. I am Dr. Senku Ishigami, and I will be teaching you chemistry.”

A squeal echoed from the back of the room, sounding like excitement. He knew of his “fame” in the academic world, but surely no child here would know him.

He picked up the student list. It was a relatively large class, with very common names. Ryusui had tried to keep the school as open as possible.

But one name in particular caught the older man’s attention in na indescribable way. His eyes widened, his mouth fell open in surprise. His lips trembled as he tried to pronounce it.

“H-Hoshi Asagiri?”

“Here!”

A hand shot up from the middle of the room. When he saw where it came from, he was startled. The girl was nothing like what Senku would imagine Gen Asagiri’s daughter to be—brown eyes, green front strands (almost too similar to his own), and a smile stretching from ear to ear.

He concluded: it could be another Asagiri family. There was no way someone as arrogant and self-absorbed as Gen Asagiri could have raised a daughter with such a different identity. The celebrity would never have enough empathy for that.

Not far away, in another room of Nanami School—the section for younger students—was Gen Asagiri.

He was smiling broadly as students filed in. Some looked at him strangely, others were impressed when they realized who he was.

But one student in particular caught Gen’s attention—the last one to enter the room. He wore childish clothes that Gen considered tasteful (he’d kill for Hoshi to wear something like that at her age). His hair was white, which was oddly normal, but the tips were black.

He walked with immense confidence. Gen noticed dominant traits in his posture and deduced he would be the “queen bee.” Without hesitation, the boy approached Gen’s desk and stared straight at him.

“Good morning, Professor Asagiri!”

“Uh? Good morning?”

“I’m a big fan of your work. I’ve read all your books and watched your shows. I believe the art of mentalism is the greatest invention of psychoanalysis and social control.”

This year is going to be interesting.

“Thank you very much. It’s good to see such a young and intelligent fan. What’s your name, kid?”

“Of course, I almost forgot. My name is Newton Ishigami, but my nickname is Ton.”

The school bell rang. Newton sat down, leaving Gen with nothing but a look of simple astonishment.

Could he be a relative of Senku Ishigami? A distant relative? Very distant?

One spark of connection later, Gen realized that no one but Senku Ishigami would name his child Newton in the middle of Japan.

While writing on the board, he thought a little more: a son of Ishigami, with public knowledge and social-psychological studies? The man with two-toned hair concluded the doctor was simply na absent father. So his child had leaned on another older figure to fill the paternal void.

 

Senku was exhausted. He had gone through four classrooms: two extremely noisy, and the other two where the students simply weren’t paying attention.

He’d get back at Xeno later for such a terrible recommendation.

But what gave him a small glimmer of hope was the supposed daughter of Asagiri—she was the only one who answered his questions and wrote down everything he asked. There was no way she could be Gen Asagiri’s daughter.

He finally reached the teachers’ lounge, which was shared with the primary school staff. He dropped his materials on the sofa, which seemed almost like na island because of its size.

Looking around, he realized his old friend hadn’t skimped on comfort for his employees. But then again, Ryusui never skimped on anything. The lounge was basically a large leisure and rest area—he could swear he saw a bed in the corner, but he was too tired to notice more.

The director, who had spoken with him earlier about the position, opened the door. The other teachers didn’t seem to care much about his presence. Senku figured the director must spend a lot of time there.

“I’d like to speak with the new teacher.”

“Yes?”

The other voice that carried across the room came from the opposite side. Senku rubbed his eyes quickly, trying to see the figure—only to be met with Gen Asagiri’s perplexed face staring back at him, completely frozen.

That sight shook away his exhaustion. This was unexpected.

Chapter Text

The ticking of the clock in the principal’s office beat heavily in the ears of the teachers. The atmosphere was apathetic; they only knew each other on the most superficial level, as characters, not as real people.

They avoided any kind of eye contact while the principal adjusted something on the shelf behind his desk. They sat side by side, but it was almost as if both of them were facing the other way.

The principal finally sat down at his desk and looked at them with a warm smile. They both turned to face him and forced a polite smile, trying to avoid the discomfort each one brought to the other.

“I’d like to officially welcome you both to the Nanami Institute. I couldn’t be here for your first classes, and I apologize for that.”

“No problem, Principal. The veteran teachers welcomed me in the best way.”

A muffled sigh, almost imperceptible, escaped Senku’s lips—just enough for Gen’s sharp ears to catch. He thought it was a petty gesture, but he expected nothing less from someone like Senku.

“We have a tradition here: every new teacher is always integrated through a school project. Since this time we have both of you, I decided to combine the useful with the pleasant.”

“What do you mean?”

They spoke at the same time, immediately surprising themselves. The principal chuckled at their synchronized reaction.

“We hold a competition at the beginning of the year, between one primary class and one secondary class against another pair. So, I thought I’d assign you two to coordinate a pair of classes together.”

It had to be cruel fate working against Gen. And monotonous bad luck working against Senku.

“What do you think?”

“I’d love that, Principal!”

“I don’t see any problem with it either.”

“Excellent! The competition will take place Friday morning. On the day, you’ll find out which classes you’ll be assigned to.”

They left as quickly as they had entered, saying their goodbyes on the way out. They couldn’t avoid walking side by side down the hallway without speaking, but eventually, communication became necessary to prevent future awkwardness.

“Nice to meet you, I’m—”

“Dr. Senku Ishigami! A pleasure to finally meet you. I’m Gen Asagiri.”

“You know me?”

“How could I not? Your research is famous. And besides, your last little ‘accident’ became quite popular online. I imagine that must be the reason for your career change.”

Gen’s sharp words hit Senku like a knife, striking a wound that hadn’t yet healed. Those half-closed black eyes, the innocent smile masking something cruel—it made Ishigami’s blood run faster, especially in his face.

He had to respond in kind to this arrogant trickster.

“I hadn’t realized my personal matters were so entertaining—quite different from yours, of course. I heard your fans were deeply worried about your disappearance after that spat with a certain celebrity. I’m glad to see you’re well and productive, Professor Asagiri.”

Their smiles were empty, but sparks and insults were flying silently between their eyes. Both were at the breaking point of their patience; it wouldn’t take much for either to leap at the other’s throat and start a full-on fight.

What saved them was the sound of the alarm bell, children flooding the halls, blissfully unaware of the tension. The teachers had to return to their classrooms.

“I must go to class now, Mr. Ishigami. I hope to see you again before Friday.”

It was a bluff. Gen wanted to see the onion-haired man as little as possible.

“See you later, Mr. Asagiri. Until Friday.”

Unlike Gen, Senku didn’t hide his emotions so well. Just enough to avoid being charged with a hate crime. He simply didn’t care about making it clear that he had no interest in talking to the older man. That kind of bluntness made Gen’s nerves burn.

They left the hallway, but not without exchanging one last look that said everything. They were furious at each other.

 

Gen was exhausted. That short conversation with the scientist had drained every bit of energy he had left.

He was nearly asleep over the pan while finishing dinner. The only thing keeping him awake was the sound of the evening news that Hoshi watched as if it were a teen drama.

The doorbell rang, catching his attention. He wasn’t expecting visitors that night, but he knew his friends well enough to guess who it was.

“I’ll get it, Dad.”

Gen watched his daughter open the door, revealing two very familiar figures. The first had well-kept blond hair, calm eyes, and na elegant smile. The other had short white hair, shopping bags Gen assumed were full of gifts for Hoshi, and na older, tired expression.

“Auntie Ruri! Uncle Ukyo!”

“Hello, sweet Hoshi!”

“I’ve missed you two so much!”

Gen turned off the stove and headed straight into his friends’ arms. He desperately needed their comfort.

“I didn’t know your boyfriends let you out at night.”

“Very funny, Gen. But you know I’m married.”

“And I’m still seeing someone.”

“Yeah, yeah. Never gonna tell me who the lucky guy is?”

“Don’t you remember, Gen? He’s too important for me to reveal just yet.”

“You two are unbearable.”

The men laughed their way into the living room while Ruri was clearly irritated—but in her usual calm, poised way. Hoshi tried not to laugh at how her honorary aunt could stay classy and still want to strangle her friends.

“How was your first day, Hoshi?”

“You won’t believe it! I had the best luck ever in academics!”

“Well, at least someone’s happy with today.”

Ukyo knew when his best friend was in a bad mood, and this time it was at worrying levels.

“My chemistry teacher is none other than Dr. Senku Ishigami himself!”

Hours passed with Hoshi still gushing about her idol teaching her class. Gen’s mood only worsened. Eventually, it was Hoshi’s bedtime. She always stuck to her schedule—eleven minutes later, she was in REM sleep.

“So Ishigami really got under your skin, huh?”

They were out on Gen’s spacious balcony. He lit a cigarette—not addicted, but it helped him relax after a stressful day.

“What did he do to get you so riled up, Gen?”

“It’s not about what he did. It’s about who he is.”

“You two already met?”

“Apparently, the school forced me to coordinate the competition with him.” His friends watched as his countless masks shattered while he spoke of Senku. “He’s exactly what I imagined: cold, arrogant, with that blank expression while listening to the principal. I really wanted to kill him right then.”

Ruri and Ukyo exchanged a knowing look. Years of friendship told them what Gen was really feeling.

“Gen, promise you won’t get mad about what I’m about to say, okay?” Ukyo’s calm eyes met Gen’s confused ones. He nodded reluctantly. “But maybe… you just want to sleep with him.”

“WHAT???”

 

The cheap alcohol Chrome had bought was already halfway gone on the coffee table. Newton had been a handful to put to bed, chattering endlessly about his beloved Professor Gen Asagiri and how he had dominated the classroom on his first day.

“What’s your deal with Gen Asagiri?”

“What do you mean, Chrome?”

“Don’t play dumb, Senku. We all saw your face whenever Newton mentioned his name.” Ryusui, who refused to drink anything under a thousand dollars, gave him that smug smile. “You’ve never acted like this before. What’s up?”

“I spoke with him today. He teaches primary school, but we’ll be working together Friday.” That wasn’t what Chrome and Ryusui wanted, and Senku felt pressured to admit the truth. “Fine. The guy’s a fraud. Fake down to the last hair on his head. For example, he always puts on that fake smile, pretending to care about what people are saying. And he even tried to fake being friendly with me!”

“Relax, man. I’ve never heard you talk this much about one person. Usually, you just don’t care.”

“Yeah, I know, but that guy makes me want to talk bad about him for hours.”

“I don’t know if you noticed, Chrome, but I think there’s another reason for all this irritation.”

“What do you mean?”

“Senku, my friend, how long has it been since you went out with someone?”

“RYUSUI!”

“I’m saying this for your own good. Maybe this hatred is just misplaced desire. You can’t deny the magician’s got some fine curves.”

“That’s it! Get out of my house. I won’t sit here listening to this nonsense about me.”

Senku wasn’t strong—not even close. But somehow, he found the strength to drag the two men to his door while they protested the whole way.

“Come on, Senku, I didn’t even mention that thing about you wanting Gen Asagiri—”

“Yeah, we won’t bring it up again. Even though it’s true.”

That was enough for Ishigami to slam the door in their faces. He didn’t need to hear another word of their nonsense. After all, he didn’t feel any of that.

There was no way Senku Ishigami and Gen Asagiri could ever be attracted to each other. How could they be? They were complete opposites.

Yet, one random afternoon during recess at Nanami Institute, two children of similar ages met for the first time. And their friendship couldn’t have been more perfect.