Chapter Text
“Come on kid, at least give your old dad a hug goodbye.”
“No way you geezer! Keep your hands off! Jeez, why do you always act like you're going off on some long journey, you’ll be two hours away!”
In spite of his harsh words, Senku did offer Byakuya a pat on the back. Still, hugging was overkill.
His father sighed dramatically with a ridiculously wounded expression.
“Are you sure you’re okay? I mean, with that chest cold you just-”
“Dad, I’m fine. Just go already before you end up late!”
“Fine, fine. Talk to you tonight, don’t forget to eat things that aren’t takeout or frozen at least twice this week.”
“Yes yes I know, goodbye, Dad.”
When he left, Senku retreated to his lab for research, business as usual.
It was a short trip, just a big celebration with his astronaut friends. He’d be gone for four days. Senku had been alone for far longer when he went to America.
He was recovering from a pretty bad chest cold, but all that was left of that now was a lingering cough. That would be gone before long, and then he’d be fine.
So why do I have a bad feeling?
~~~
He slept poorly for some reason, and he woke up exhausted. His cough was worse, his skin prickly with heat.
Crap, I can’t get sick again.
He lost so much time at school already, he was behind on so many projects with the science club. (Actual classes were no problem, and neither was homework– he could easily pick up on the current lesson even when he missed class. And homework he could catch up on in an hour tops.)
He had to go. He’d take medicine (over the counter medicine he’d enhanced himself) and tough it out.
~~~
Senku coughed all day. Everyone kept giving him worried looks, especially Taiju and Yuzuriha.
He knew he was sick, he regretted coming but he was here so he might as well push through it.
If he went home, the school would call Byakuya, who was already nervous about being away. He was too close to finally going to space; Senku couldn’t get in his way by making him worry.
PE was hell, as always. Running laps always made him feel like his legs would fall off. But today it made his lungs feel like they were full of nitric acid. (An illogical metaphor, seeing as if that was actually the case, he’d be dead.)
He went to the bathroom afterwards and coughed for a full two minutes. Something yellow and mucus-like came up near the end. That wasn’t good.
Just a few more hours…
~~~
He dragged his feet on the way to Science Club– normally his sanctuary, but today it filled him with dread.
Thinking about all those fumes…
He ran into one of the other members, who greeted him with a wave.
“Hey prez! Did you miss the memo? Clubs cancelled today, they’re cleaning the room and the equipment.”
Senku nearly fainted from relief. All the fumes and chemicals might’ve actually killed him today.
“Ah… what a shame. See you tomorrow then.”
Before he could walk away, the worried voice called out.
“Are you okay? You look pale, and I thought you’d be more upset. Not to mention, you’ve been coughing all day.”
“Just a chest cold I can’t shake… See you.”
He walked away before he could be pressed further. He’d rather keep talking to a minimum right now anyway.
~~~
Finally home… Senku flung off his lab coat and backpack, then threw a Cup Noodle in the microwave for dinner before collapsing into bed.
He was exhausted, completely and utterly.
He thought there might be something he was forgetting, but he’d worry about it tomorrow.
Unfortunately, he slept terribly. He kept going between hot and cold, he couldn’t get comfortable no matter how he adjusted, and of course the coughing.
It was a very long night.
~~~
Senku was even worse the next morning.
It was only when he coughed up more yellow mucus that he accepted the fact that school would not be possible.
He needed to call them but he’d do it later. He didn’t much care about the consequences right now.
His head was hazy as he dragged himself back to his room from the bathroom. There was something he needed to do, what was it?His body felt so hot, his brain felt like it was boiling… Boiling… He was hungry. Maybe he should boil water and make noodles. He still had to follow the two meal rule.
(His dad insisted he eat at least two meals a week that weren’t frozen or take-out when he was away. He couldn’t really enforce that rule, but he’d be miffed if Senku didn’t follow it. And in spite of how he acted most of the time— Senku didn’t like seeing his dad upset if he could avoid it.)
He somehow made it to the kitchen, he managed to fill the pot, but once he had to lift the full pot up everything fell apart.
A horrible coughing fit overtook him right as the pot was in his hands, it went crashing to the floor and Senku went with it.
He felt… pathetic. Laying on the floor in the spilled water, coughing so hard he could feel his rib cage rattling.
I wish Byakuya was here…
Oh shit! I forgot to call him!
That was the one, fundamental rule while Byakuya was away. He had to call every night so his dad knew he was okay.
He was in so much trouble. Byakuya was going to be pissed.
Senku dragged himself to where he’d abandoned his bag and retrieved his phone. He somehow made it to the couch and collapsed onto it. Then, he finally worked up the courage to look at the phone.
Seven missed calls, dozens of texts. At the very moment he looked at the screen it lit up with Byakuya’s name.
“You better have a good reason, young man. And don’t say research. Do you have any idea-“
“I know, I’m sorry I—” he broke into a coughing fit.
“Oh my god… you sound awful.” The anger was gone in an instant, replaced by deep concern.
“I- don’t know what's— cough— wrong with me. I feel awful.”
Actually something told him he should know, but his brain was so foggy he couldn’t grasp the thought.
“How long have you felt this bad, and what are your symptoms? Talk slow, don’t push yourself.”
“Yesterday morning… it was bad all throughout school…this morning it was— cough— worse. It’s hard to breathe… I can't stop coughing and I have a fever…”
Another fit overtook him, he held the phone away from his face until he caught his breath.
“Can you hang in there for a couple hours?”
“Until what?”
“Until I come back of course!”
“No… I’m fine… you don’t have to-”
“Kid, you are way too smart to say something that dumb. Your breathing sounds like a bunch of rocks rattling around in a cage, I can hear it over the phone. You are not fine. I’ll be back soon, so get a cold compress and a water bottle, go to your room, and don’t move until I get there. Got it?”
Senku’s eyes burned for some reason.
“Okay…”
“I’ll stay on the phone with you until you get settled, just hang in there, Senku. I’m coming.”
~~~
Byakuya pushed the boundaries of the speed limit in his rental car. The only reason he didn’t outright break it was because getting pulled over would make it take longer to get to Senku. He’d quickly told the rest of the group that he had a family emergency, grabbed his things from his hotel room and now here he was.
Senku sounded awful on the phone. His breath rattling, his voice thin and weak. And the first thing he said was “I’m sorry” which wasn’t like him. It also wasn’t like him to miss their calls. Sure, he was a troublemaker at times. (In alarming ways like accidentally blowing up his room.) But he wasn’t a bad kid. He simply put science as his highest priority, and sometimes that passion got carried away.
So breaking Byakuya's one most important rule was unusual.
Two hours never felt so long.
~~~
Byakuya threw open the door to the apartment. Senku’s backpack lay abandoned by the entrance, along with his lab coat.
As he walked through the house he spotted a mess in the kitchen, a pot laying in a puddle of water. Was he trying to cook?
He heard footsteps, the sound of someone slowly walking. He rounded the corner.
Senku shuffled along the wall, looking even worse than he’d sounded over the phone.
Pale face, sunken cheeks, and his eyes… Those crimson eyes normally full of a spark of intelligence were so dull they were practically brown, glassy and hazy.
Byakuya rushed forward, and as he reached the boy, Senku collapsed into his arms.
“Whoa now- easy Senku, why are you up?”
He held the boy close to his chest. The heat radiating off his body was alarming.
Senku didn’t reject the hug, in fact, he gripped the back of his father’s shirt tightly, burying his face in Byakuya's shoulder. Another alarm bell went off in his head.
“I— cough— heard the car so I-” more coughing, Byakuya cupped his head.
“Let’s get you back to bed, kid. I’m here now, it’s gonna be fine.”
After helping him to his room, Byakuya checked his temperature with the thermometer.
He was shocked by how high it was. He shouldn’t have been, but he was.
He looked down at Senku’s pale face– his breath sounded even worse than it did over the phone. Contemplating taking him to the hospital.
If he gets much worse I’ll have to, but for now I’ll see if finally having someone take care of him will help.
He set him up with extra pillows, which seemed to help him breathe somewhat. He called a friend to pick up medicine. He cleaned up the mess in the kitchen and got some soup going. He tended to Senku with a cool compress and a humidifier.
Poor kid was pretty out of it; he accepted the help without complaint. He finally fell asleep not long after the humidifier.
Byakuya brushed the few strands of hair that clung to his face away, watching his breathing carefully.
Maybe this was actually working.
And then of course it fell apart.
His fever spiked right as Byakuya was bringing him dinner, and then he broke into a violent fit so bad he couldn’t catch his breath between the coughs.
Something came up at the end of the fit, something red.
“Hey- what’re you-”
Senku started to protest as Byakuya picked him up ( not easy, when did he get so big?)
More coughing stopped his complaints, Senku sank his head into his fathers shoulder with a faint groan when it finally stopped.
He didn’t complain any more after that.
~~~
Senku rested his cheek against the car window. It felt wonderfully cool against his hot face.
Everything was so hazy now…
He was half aware of Byakuya giving him worried looks as he drove, he would’ve liked to tell him to knock it off, but he simply didn’t have the breath for it anymore.
Was he dying? Was this what dying felt like? He certainly wasn’t breathing enough, depriving oxygen to his most valuable weapon: his brain. So figuring out what was going on felt a bit beyond him right now.
He was tired, maybe he could sleep a bit…
“Hey! You stay with me!”
How annoying, he just wanted to rest his eyes. Surely it couldn’t be that bad to rest a little.
His eyelids were so heavy… just a few minutes wouldn’t hurt…
“Senku!”
Byakuya's frantic cry never reached his ears.
~~~
Something hard and plastic pressed against his face, and something was stuck to his arm that itched. The air smelled of antiseptic and medicine.
Senku opened his eyes, greeted by sterile white walls and ceiling.
A hospital room, that’s where he was. His head was a bit clearer, since he was able to deduce that.
He also was not alone. Voices drifted over from nearby.
“Stable now…”
“When will he…”
Senku shifted, making the bed creak, which got the attention of the other two.
“Senku!”
Byakuya rushed over, gripping Senku's hand tightly.
Senku wanted to say something, but his mouth wasn’t working. The oxygen mask would probably muffle him anyway. So he just locked his eyes onto Byakuya’s, and squeezed his hand. More affection than he would normally offer, but he wanted his old man to know he was okay.
Mostly, anyway.
The Doctor did some tests and asked a few questions, and then he left father and son to themselves.
“How are you feeling? You scared me half to death, kid. Oh wait, you can’t answer that can you? Hang on a sec.”
He helped Senku adjust, removed his mask for a moment, and helped him drink a glass of water.
“I… feel like shit… not as bad as you look, though.”
“Well clearly you’re feeling at least a little better, if you’re back to talking smack.”
Senku smiled a little. He still felt horrible, but his head was clearer now. And… his dad was here now. He'd never, ever , admit it out loud, but that was a huge relief.
He really did look rough, though, his hair was a mess, his goatee looked less groomed than usual, and he had dark circles under his eyes.
“How long was I..?”
“Well we got here last night, and it’s noon now.”
“What!?!” Senku cried,and then coughed.
Byakuya patted his head, and then put the mask back on.
“You needed it, kid. Now you need to keep resting. You have pneumonia. If we didn’t come in when we did you might have needed surgery. If you rest you’ll be able to go home in a week or so.”
Senku would have liked to protest, but it appeared his body was on Bukuya's side. His eyes were already half lidded and aiming to be fully closed soon.
“Rest. I’ll be here when you wake up.”
And so Senku obliged, both the will of his father and of his own body.
~~~
After two days, he didn’t need the oxygen mask, three days after that he was sent home.
Byakuya sent him directly to his room as soon as they made it back. He set him up with a water bottle, a humidifier, and a cool compress on his head.
Senku was restless, but too tired to do anything about it. He’d have liked to go back to his usual research, but even that was much right now, as was homework Taiju and Yuzuriha had brought him.
This… sucks.
“Holding up okay?”
Byakuya entered the room with a bowl of miso soup and rice.
“I’m— cough— alive…”
“Well, let’s count all our victories.”
He set the tray on Senku’s lap.
It was a comforting meal, better than what Senku had been planning to eat while his dad was away, and infinitely better than hospital food.
Byakuya watched him with concern.
“Quit gaping at me, old man.”
“Sorry.” Byakuya looked away.
That was… not the reaction Senku wanted. He expected Byakuya to have some sort of comeback or retort.
His old man had been acting weird all week. It made sense when he was in the hospital, but he thought it would be better now that he was home.
Senku didn’t like it at all.
“Do you… feel bad that I’m sick? Or something?”
Byakuya shook his head. Not looking Senku in the eyes, he said,
“That’s not quite it. I shouldn’t have left you, at least not until I knew you were healthy again. And then I screwed up again by not taking you to the hospital right away. I’m… not feeling like the best dad at the moment.”
“But… we thought I was better! You couldn’t have-”
“Even so, making sure you're healthy and safe is my job. There’s about ten billion things I could have done differently.”
“That doesn’t make you a bad dad! You… put up with all my bullshit, I know I’m… not easy to deal with and yet for some reason you haven’t ditched me! You-”
A coughing fit overtook the rest of his words, Senku was completely exhausted by the time it passed. But… he didn’t regret it.
Byakuya's eyes looked a little misty.
“Thank you, Senku. You have no idea how much those words mean. Especially from a cold kid like you! Now finish your dinner and get some rest. If you need anything at all, just call me, okay? I’m here, and I’m sticking with you until you're well again. I’ll always be around when you need me.”
Senku nodded, too worn out for any more words. Byakuya gave his shoulder a gentle squeeze.
He seemed to be in a better mood from then on, and that… made Senku happy.
~~~
His recovery went smoothly after that. Within two weeks he was back on his feet and going to school again. Byakuya's departure for, well, space was fast approaching, so they actually spent some time together, and Senku didn’t fight it like he normally would.
They lived in blissful ignorance of the green light that soon would sweep across the planet, separating father and son by thousands of years.
~~~
“I’m going to space for god's sake! At least give me a hug goodbye!”
“Ugh, fine , you get two seconds.”
That seemed to make Byakuya happy, so Senku didn’t mind that much.
“Please try not to blow up the apartment while I’m gone. You’ve got all the emergency numbers in your phone, right? And seriously, try to eat decently!”
“Yes, I know, we’ve done this ten billion times before.”
“But this is different, you can’t call me if there’s trouble. I gotta admit… that freaks me out a bit.”
Senku shook his head. This was different, but it was his dad’s dream. And Senku himself had put in quite a bit of effort to make it come true.
He wouldn’t be the reason he stopped now.
“If I have an emergency, I’ll build myself a rocket and come get you.”
Byakuya laughed, clapping Senku on the back.
“You would do that, wouldn’t you? See ya, Senku. Don’t forget to watch the takeoff livestream!”
“Nah I’ll be too busy. Bye, Dad.”
He left a moment later, Senku thought nothing of it as he made his way back to his lab.
He had to investigate that swallow statue he found.