Chapter Text
Senku leans back in his chair, rubbing at his eyes. It’s 7PM, which is early for him to be so tired, but he’s been looking at his model since 11AM and hasn’t moved much. His back is stiff and he’s slightly dehydrated.
His computer screen is still showing “wait” while it processes his latest changes to his model and shoves it through the supercomputer he’s been renting time on. The sky is dark outside his window, the clouds glowing with the endless lights of Tokyo spread out below. Spring is underway, although not to the point where the city can be considered beautiful yet. Mostly it’s a little gray, a little touched by the scent of coming warmth and new growth.
He’s been ignoring his actual research and the paper he needs to finish in favor of his side project that his lab director hasn’t approved. He’s just starting to find a groove, though, and while the turbulence of plasma around black holes is fascinating, so are wormholes. He suspects Ryusaui Nanami, who funds the Space Futures lab and all of Senku’s research, won’t care about a wasted day or two if he finds something interesting. Ryusui is often easily distracted by interesting new facts or new avenues for work. He once skipped a business meeting to listen to post-doc Chelsea describe how to use satellites to map new worlds’ geographies.
He props his chin up on his hand and watches the screen through half-lidded eyes. The model is only theoretical, but Senku’s long been interested in wormholes and their potential to solve space-travel issues. He’s been fascinated by whether they exist or not - he understands they’re consistent with relativity, but if they could be stable enough to travel through is another question entirely. He’s been experimenting with this model for a while, trying to see if anything could be demonstrated that a wormhole could theoretically be used for interstellar travel.
The model chirps - a little noise Senku added to the code to let him know when it’s finished processing. He opens his eyes and checks the results, feeling tired. It’s the fifth time he’s run the model today, making some tweaks to his inputs and assumptions every time.
But now something seems different.
His modeled wormhole seems stable. And it’s large - about the size to fit a human being. Senku’s breath catches. His work shows that there’s a possibility that a human could travel through one, without exposure to any exotic matter.
It’s small. But all scientific discoveries start small before adding up to something huge. For something Senku has been experimenting with in his spare time, this achievement is significant. He could even bring this up to his lab director, maybe actually direct a portion of his time to this without needing to sneak it in as he can. Taiju is going to freak out when Senku tells him the model is theoretically sound.
Senku, though, immediately knows who he wants to talk to. He’s alone in the lab on a Monday night, and there’s one person in the world he wants to talk to about what he’s achieved. He pulls out his phone, pulls up his dad’s WhatsApp contact, and hits “call”.
The ring sounds. Senku taps his fingers on the desk impatiently, waiting for his dad to pick up.
“Ergh….hello, this is Ishigami Byakuya.” Byakuya sounds groggy as hell, and Senku winces. Right, there’s a huge time difference between Japan and Florida. It must be early - Byakuya has always been an obnoxious morning person, but even he has his limits.
“Sorry, old man, forget you’re not a rooster up at the crack of dawn,” he says instead. For whatever reason, that’s about as compassionate as Senku can ever let himself sound.
“Senku! Oh, fuck you,” Byakuya says good-naturedly, sounding more awake. “My alarm was going to go off in twenty anyway. What’s up?”
“Dad,” Senku says, straining to keep his tone level, despite his headache and the excitement still pulsing through him, “The model works.”
“No way!” Byakuya gasps. “Wait, which model is this? Your plasma turbulence one or the super-duper secret wormhole one?”
“The one I’m not supposed to be working on during work hours. But it’s showing that a theoretically stable wormhole is possible and would be large enough to fit a person."
Byakuya whistles, impressed, and Senku has to bite back his grin. His father is always so direct and proud of him.“Amazing. I’m looking forward to whatever paper you write on this. Look at you, changing the world.”
“Ugh, no, I just made a model. It’s all still theoretical right now.”
“A model is the first step on the journey to reality,” Byakuya says sagely. Senku can hear the rustling of blankets - his dad must have just decided to get up.
“You’re also the one who told me all models are wrong, but some are useful. Is Lilian with you?”
“No, she’s still wrapping up production on her album in California. She will be coming with me back to Japan in three weeks, though!”
“Ah, Yuzuriha and Taiju will be delighted to hear that.” He can’t say he is too, too cringy. His dad is genuinely so happy with Lilian - Senku likes her music well enough, and she seems to be a kind person, but she’s hard to get to know. Or perhaps that’s been on him. She’s not particularly into video games and while smart, has a pop-culture understanding of science, so Senku often isn’t sure what to say to her. They often end up talking about the weather, how she finds Japanese food, or whatever silly thing Byakuya last did for either of them. It’s much a microcosm of how Senku gets along with most people who aren’t Taiju or Yuzuriha.
“We’ll have to have a lot of dinners with you all. Lilian is excited to see the cherry blossoms, too. She’s considering naming a song on the album after them. Anyway, thanks for calling, kiddo. I should probably get up and get to my Soul Cycle class. Cindy’s going through a divorce so we’re trying to exercise out all her rage.”
“Yeah. See you, dad.” Senku hangs up and sits there in the half-darkness, staring at his screen for a moment. The model’s results still look like how they did before - a theoretically incredible accomplishment that for now is mostly just text and numbers. His brain feels fuzzy, and he’s suddenly hyperaware of how thirsty and tired he is. He feels oddly sore and understandably stiff, and he can’t help but grunt as he slowly gets to his feet and grabs his bag and his too-light jacket.
He pulls out his phone as he leaves the physics building and starts walking down the street. It’s long since dark, and the air is chilly. He selects Yuzuriha’s contact as he adjusts the collar of his jacket to not press so uncomfortably into his neck. She picks up at the third ring.
“Senku! Hi hi. Are you eating at home or out?” Yuzuriha asks chirpily. “Taiju and I are making tonkatsu - Taiju will eat your portion if you don’t want it.”
“No, probably not. I’ll probably eat at Taro tonight.” He’s been living with Taiju and Yuzuriha since college, splitting an apartment that’s slightly too large for the three of them. He suspects he was wrangled into this because Yuzuriha seems convinced Senku won’t eat if she and Taiju aren’t around to remind him to. It’s not odd, living with a couple - he’s always had a good relationship with them, both together and separately, and lab work keeps him so busy he’s barely there anyway. But it can seem that way, to people who don’t know him and his friends, the ways in which they make each other’s lives better and more complete.
“We’ll see you when you get back then. If you pass a convini, can you snag some rice balls for Taiju? He has a 7AM start time tomorrow.”
“Gross, what person wants to be in the gym at the crack of dawn?”
“Taiju, usually. And you can’t talk, I know you’ve gone into the lab before sunrise. Text me when you’re on the train back, please.”
“Yeah, yeah, I will. Don’t let me keep you from dinner - Taiju might set the stove on fire if you’re not watching him.”
Yuzuriha laughs, cheerful and upbeat. Senku tries to suppress his smile. “You know him so well. See you later.” She doesn’t wait for him to say anything more and hangs up. Moreso than Taiju, she’s always been aware of how Senku likes to communicate, his limitations on sentimentality. Senku tucks his phone in his pocket and continues to walk down the street towards Taro.
The izakaya is about half-empty when he enters, people crowded mostly around the low tables, leaving the bar seating largely open. Senku nods to the usual waiter and settles in at the end of the bar. He glances around the room while taking off his jacket, and pauses momentarily when he notices one of the people sitting in at the table near the back.
He’s pretty sure that’s Asagiri Gen, the famed mentalist, picking at some sashimi and fried eggplant, looking tired and pale. Taiju and Yuzuriha are big fans of his show - Lilian has bought them tickets in the past, and they like watching his specials. Yuzuriha has copies of his books, one of them signed. Senku can’t say he’s the biggest fan - he thinks Gen comes off as either a genuine idiot, or someone dumbing down his intelligence to coast on by.
In person, though, it’s hard to deny there’s something magnetic and eye-catching to him. The white half of his hair is startling under the lights, the black half dark and shiny. His skin is clear, despite the slightly lilac bags under his eyes, his sharp gray eyes surprisingly cunning. He’s wearing a cream-colored turtleneck and a pale yellow scarf, a thin gold waist chain spilling onto the floor. A light purple jacket is hanging from the wooden divider behind him. He looks more thoughtful than he does in his shows, nodding to something his companion is saying - a man with shockingly platinum hair in a yellow sweater.
Senku briefly debates taking a picture so he can show Yuzuriha, and then immediately dismisses that as creep behavior. Taiju and Yuzuriha never doubt him anyway - there’s too many years of trust between them, and Senku has never been one to claim something solely for attention. He purposefully turns back to the bar and orders kaarage, grilled fish, edamame and a beer.
Senku’s mind drifts while eating, dwelling on the paper he should be writing but isn’t, the wormhole model that’s working, the awful triathlon he’s training to do to keep up with the astronaut physical fitness standards, the fact that he’s 27 and his best friends are moving towards marriage and he’s still living with them because no one trusts him to handle life by himself.
His life is not bad. His research inspires and drives him. He spends most of his days working on his physics simulations, but he’s able to use the chemistry labs to keep up with that, thanks to his second master’s in chemistry. Living with his friends is pleasant - Taiju works odd hours as a personal trainer but always has time to cheer Senku on when he forces himself to run. Yuzuriha’s fashion-designer career is finally starting to take off, but she still makes time to ask Senku how his experiments are going. His dad frets about him being lonely, but he’s not the type to push Senku to get into a relationship - he’s more the type to cling to him while they’re in the same country, yammering away about how magnificent he thinks his son is.
It doesn’t quite feel like something is missing, but more like something could be added. He’s not sure what it could be. To say romance feels cringier than he wants, but maybe he just wants a connection - someone who can meet his intelligence halfway, where he doesn’t have to spend half an hour going through the minutiae to get to the novel piece of information that’s exciting him.
He mocks Taiju mercilessly, in the way expected by male friendship, but he has that flow and fit and comfort with Yuzuriha. They’ll look at each other while he’s helping her wrap up a craft project or as she’s helping him organize his clients’ customized fitness plans and just smile at each other - these secretive little things that feel like something for just the two of them. Senku always feels distinctly like he shouldn’t be there when he sees those smiles. He knows they love him, and he loves them, but that’s a moment for two people, alone in their bubble, secure in what they share.
He pays and gets up to leave. It’s not late, but he’s worn out. The staff calls after him cheerfully as he slides open the door and steps into the brisk evening.
Senku sighs sleepily, waiting for the light to turn. His breath steams in the air. The roads are quiet now, or as quiet as Tokyo can get. He’s still got a ten minute walk to the station and then a twenty minute ride home. It’s early spring, and the air is not quite chilly enough to warrant feeling so cold, but Senku suddenly wishes he had listened to Yuzuriha this morning and had taken the scarf she’d just finished knitting for him.
He can sense someone standing near him, also waiting for the light. In true fashion of someone who has lived in a city their whole life and doesn’t want to have any eye contact, let alone a conversation, Senku keeps his eyes on the crosswalk ahead of him. The streetlight next to him is flickering, creating a pool of amber that blinks into darkness and back into light.
The light turns, the walk signal flashing, and Senku steps out into the street, shoving his hands into the pockets of his jacket, mind already on what convini he should stop by to get Taiju’s riceballs.
There’s things you just trust, living in a city like Tokyo. You have to - the city is vast and complicated, teeming with every type of political belief and fashion subgroup, just barely held together by the veneer of civilization and the power of social shame. You have to trust that lights will work, that drivers will obey laws. You trust that in the way that you trust the sun will come up, even if it’s cloudy.
Senku, therefore, barely even thinks of reacting as a car lurches forward down the almost-empty street at full speed, horn blaring, charging straight towards him. He’s never been in a situation to fully grasp fight-flight-freeze-fawn, but all of a sudden, he recognizes how overpowering instincts can be.
Unfortunately, his instinct is to freeze. His joints seem to lock up, his muscles as still as if he’d been dipped in liquid nitrogen, and all he can do is stare as the blinding headlights barrel closer at what feels like the speed of light.
Thankfully, it isn’t the reaction for the other person standing at the light with him.
Senku feels a hand clamp around his arm and yank him backwards so firmly he almost falls onto the asphalt, only held up by whoever has him in their grasp. He can feel the breeze from the car blasting past him, ears ringing from the blasting of the horn and the squealing of the brakes. He can feel his blood rushing, heart pounding, as he heaves in a suddenly terrified breath of air.
The car screeches to a halt fifty feet away, leaving behind an echoing silence. Senku stares at it and the flashing hazard lights, feeling light-headed, before turning to see who had pulled him so neatly out of danger’s path.
“Are you okay?” Gen Asagiri asks, gasping. He’s so pale, sickly under the streetlights. His hand is shaking where he’s gripping Senku’s upper arm.
“Your reflexes are better than your books, at least,” Senku replies shakily, and immediately feels a bizarre spike of shame. Gen just saved his life, there’s no reason to be a dick. Taiju is going to be so disappointed in him if he ever hears about this.
Gen’s pale gray eyes narrow, their gleam intelligent and assessing, although his hand is still trembling. “You’re a little rude to your savior, Mr. Almost-flattened-by-a-car.” He lets go of Senku’s arm. The warmth of his hand lingers, comforting in the face of a near-death experience and a chilly evening. There’s the sound of a car door slamming and then frantic footsteps. Senku can’t bring himself to be anything other than mildly shocked rather than curious.
“Oh my god, I am so sorry!” The driver of the car looks like he’s about to hyperventilate, sweaty and shaking. “My car’s controls just took over and over-rode my brake! I don’t know what happened, it’s a brand-new Corolla!”
“Take it to the goddamn shop before you seriously hurt someone,” Gen snaps, spots of color high on his cheeks. “You shouldn’t be driving that if it’s not working!”
“But it should be,” the man blubbers, looking close to tears. “I am so, so sorry. I’ll call the mechanic in the morning.”
“Make sure you do,” Gen says firmly. It’s clearly a dismissal. The driver slinks away, sniffling heavily. Gen glowers after him for another moment, and then turns to Senku. “I feel at a disadvantage, dear. You clearly know of me, but I have no name for you. Shall I call you bastard-chan, given your sass?”
Well, not like he doesn’t kind of deserve it. “Ishigami Senku,” he says, adjusting his jacket. His arm is still warm where Gen grabbed him. “I ten billion percent would have not survived getting hit by that car since it was going too fast, so your reflexes are appreciated.”
“Mm, even if my books are not,” Gen replies coyly, adjusting his scarf and smoothing his hair down. He looks much calmer. He’s no longer nearly as pale. Either the rush faded quickly, or he’s better at controlling himself than Senku had given him credit for.
Senku sighs. “Alright, that was rude of me.”
“Indeed it was. Well, it seems like you might need supervision to walk alone at night, Senku dear. Can I accompany you anywhere?”
God, Taiju would absolutely lose his shit if Senku turns this down. Nearly getting hit by a car and then rejecting Asagiri Gen? “Fine. I was heading to the train station. You can walk me there if you must, magician.”
“You are indeed rude!” Gen sighs heavily, shoving his hands into the pockets of his purple jacket. The light changes again, the walk signal up. No cars screech ahead this time as they cross the road. “I’m not a magician, I’m a mentalist. There’s a difference, dear.”
“Is there?”
“You seem mighty uncultured, so forgive me if I don't accept your critiques. My books are quite well-reviewed, you know.”
“So was The Secret,” Senku grouses, hoisting his backpack straps up a little bit more and burrowing into his jacket. The shock is starting to wear off and he feels a little nauseated.
“Goodness, you must be fun at parties,” Gen tuts. There’s a slyness to his eyes, a tilt to his mouth. Senku would probably delight in the challenge he’s presenting if he wasn’t so exhausted.
“Fuck off, I almost died tonight.”
“Are you always this filthy around strangers you’ve just met, or am I special?”
Senku pauses mid-step, and heaves a sigh. Gen stops and turns around to glance at him, a thin smile on his face. He’s very slightly taller than Senku is, lean in a way that looks fashionable rather than malnourished. He’s glamorous and refined, and Senku feels very aware of the fact he didn’t brush his hair and his t-shirt is ripped under his jacket. “...I’m sorry. I don’t mean to be rude. I don’t talk to many new people.”
“Does anyone in this city?” Gen asks, somewhat rhetorically, gesturing about grandly. “Practice makes progress and all that.”
“Hm. Well, if you walk away deeply insulted, I ten billion percent warned you.”
Gen grins at him, delighted. “We’re almost to the station and so far you’ve insulted my job and my books, yet I’m somehow still here,” he points out, and gently nudges Senku into walking again. The touch of his gentle fingers poking into his arm sparks something in him - could be annoyance, could be intrigue. Senku squashes it immediately.
“I hadn’t realized you’re a masochist. That hasn’t come across in your shows or interviews, not even a millimeter.”
“For someone who thinks my work is garbage, you sure seem familiar with it, dear Senku.”
“My friends are big fans of yours,” he admits reluctantly. He hopes Gen doesn’t offer to sign something for them. It’d be oddly humiliating, and he would definitely have to tell Taiju how rude he had been. “They’ve taken me to see you twice and they watch every one of your shows.”
“How delightful,” Gen remarks, sounding genuinely pleased. “I’m glad they like me so much, even if you’re deeply unimpressed.”
“Ugh, magic shows just aren’t my thing. You seem too smart for TV anyway.”
“Hm, well, many smart people go on TV for a variety of reasons, my dear. To gain fame, to spread a message, to bring attention to ideas. It’s hard to fund anything in psychology, particularly now after the replication crisis in the research.” Gen sounds so nonchalant, and Senku’s mind catches on his words.
Ah. Gen is someone who takes his field seriously, and respects it, despite being aware of the limitations. Gen wasn’t dumbing down his intelligence at all, or playing it up - he’s just cautious in a way Senku, focused on the physical sciences, has never had to be.
“I wasn’t aware you were up-to-date on psych research,” he says instead.
“Ah, well, I have been working towards a PhD on and off for the last five or so years,” Gen says, as if this isn’t a shocking revelation. “It’s very hard while working full-time, of course, and the fame I have garnered to now can be a limiting factor in having time to put into it.”
“What’s your thesis?” Senku’s more intrigued than he should be. He’s deeply drawn to people who are passionate and knowledgeable about whatever they’re into - Taiju into weightlifitng, Yuzuriha into fashion, and apparently Gen.
Gen tilts his head and smiles at him, a bit more genuinely than he had earlier. “An academic yourself, are you?”
Senku’s not sure what gave him away, but feels he can’t give Gen the satisfaction of asking. “Unfortunately. Answer the question, mentalist.”
“So pushy!” Gen throws up his hands and sighs theatrically. “I’m interested in the psychology of TV and how it impacts parasocial relationships. As this conversation has so astutely demonstrated, people think they know someone who they see on TV all the time.”
“I’m surprised you didn’t use your magic psych book as a primer.”
“I’m in a unique position, what can I say?” Gen says, a bit more reflective. “It’s fascinating to be on TV and to have so many people think they know who I am, without realizing they’re seeing what I want them to see. It’s a bit more of an interesting topic to explore. It’s been helpful for writing survey questions, being on this particular side of the parasocial relationship.”
“Aren’t you worried I’ll spill these secrets?” Senku asks. He’s not aware if Gen’s research is common knowledge. It must not be, or Taiju or Yuzuriha would have likely mentioned it. They had gone on an odd campaign for a while to try and get Senku to like Gen, and they would be the type to think academics are the way to his heart.
Gen snorts. “It’s not a secret - my name is on some papers and it’s a fact that shows up when you Google me. Just no one really cares. My manager thinks I’m wasting my time.”
“Why are you doing it then?” They’re almost to the station. Senku can see it in the distance. He finds himself wishing the walk was longer, wonders how obvious it would be if he slowed down to make the last few hundred feet last.
Gen pauses, purses his lips. “Well, fame won’t last forever,” he says after a long moment, “Or at least not in this shape and form. I can’t become Japan’s Dr. Phil without the degree!”
Senku gets the strange feeling that’s not the full truth. There’s something to the set of Gen’s mouth, to the look in his eyes, that says there’s something more to it. But he just met Gen, was saved by him, insulted him. Gen doesn’t owe him anything, even if Senku feels his familiar curiosity bubbling through him like a bottle of shaken cola.
“Well, here we are,” Gen says, waving grandly at the station. “A delight to meet you, my dear Senku. Don’t get hit by a train just to prove a point - I can’t always be there to save you.”
Gen leaves him then, turning away with a little finger wave that he makes look effortlessly cool and would be unbearably dorky if Senku tried it. Senku waves after him, feeling odd, off-center. It feels like something’s shifted, but he’s not sure what. There’s an edge to the air, or maybe that’s just him, still breathing through the fading adrenalin.
The train ride passes in a blur. He stops by a 7-11 and gets Taiju three onigiri for tomorrow, like he told Yuzuriha he would.
The apartment is quiet when he arrives - Taiju and Yuzuriha must have gone to bed a while ago. Senku sneaks in, opening the refrigerator as silently as he can and putting Taiju’s riceballs in at roughly his eye level before creeping across to his bedroom.
His bed is unmade, but that is the least of Senku’s worries. He shucks off his clothes and falls into his bed. His sleep is dreamless, tinged with unease. There’s an odd sense of something eerily out of place.
His alarm goes off. Senku groans, rolling over to smack at his alarm clock. The light outside is gray and cloudy, much as it was the day before. He can hear Taiju bumbling about in the kitchen - which is odd, Senku thought he had an early client meeting today. Maybe it got canceled.
He sits up, grabbing his phone and blinking blearily at the screen, rubbing at his face while his brain comes online. Then his eyes narrow as he catches on something.
The date is March 18th. That’s what it was yesterday.
He opens his phone and scrolls back into his recent calls. It’s recording his last phone call with Byakuya as being three days ago. Yuzuriha tends to call him every night around 7:30PM to check what he’s thinking of doing for dinner, but if it’s March 18th, that means yesterday was Sunday, not Monday, and he’d not gone to work that day - he had stayed home all day and helped Yuzuriha fix her loom.
He turns the screen off and taps his phone against his lips, fighting the urge to smile.
A mystery. He could use one of those. Potentially Taiju’s meeting just got rescheduled. Potentially it’s just cloudy another day. Potentially something just went wrong with his phone, misrecording the time and his phone logs.
But also, potentially not.
At his core, Senku is not someone who is afraid of questions or uncertainty. He doesn’t shy away from not having an answer. Mysteries inherently are meant to be addressed. But he won’t begin to solve this by lazing around in his bed.
“Yo Senku!” Taiju calls cheerfully, knocking too loudly on his door. “Do you want eggs?”
Senku swings his legs out of bed. “Be quiet, big oaf, or we’ll get another noise complaint,” he says back, repressing his smile when Taiju splutters.
He gets up to restart the day. No point in lingering - there’s either a mystery to solve or a kitchen to salvage from Taiju’s wreckage.
Time usually waits for no one.
Usually.