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“Oi, Byakuya,” Senku mumbled, raising an eyebrow. The eight-year-old crossed his arms as he looked up at the catastrophe waiting to happen. “What are you doing?”
His dad beamed, despite the wobbling boxes beneath his feet. “Ah, Senku! How was school? Wasn’t today-”
Crash.
“Ow…”
Senku slid the backpack off his shoulders as Byakuya picked himself up with a groan. A dent in Senku’s mattress was all that remained of his dad’s makeshift ladder.
“You’re never gonna make it to space if you start breaking bones, old fart.”
Byakuya winced, rubbing his lower back. He certainly wasn’t getting any younger. “Ah, well…”
Atop the bed laid a pile of white plastic stars, at least a few dozen of which were already stuck to the ceiling. They certainly weren’t out of place in a room like Senku’s, surrounded by NASA posters and model rockets, but they didn’t quite match the maturity of the bedroom-turned-science lab.
“Stars?” Senku picked one up, examining it curiously in the light. “Not that they actually look like this…”
Ever the optimist, Byakuya grinned as he started cleaning up his mess. “So? You can still like the shape. I do!”
“But it’s a bit childish, don’t you think?”
Byakuya knew better than to suggest his eight-year-old son was, in fact, a child. Just what kind of third grader studied rocket engineering anyway?
“They’re cool, Senku! Just wait and see. It was supposed to be a birthday surprise, but I guess it’s too late for that now, huh?”
“Well, what’s so special about them anyway?”
The question was clearly a cue that Byakuya had been waiting for. Giggling, he gestured for Senku to sit, like a magician enticing his audience. Senku humored him and obeyed, letting his feet dangle off the side of his bed as Byakuya closed the window blinds. Then, with the flip of the light switch, the room fell into just enough darkness for a light green glow to emerge from the dozens of stars.
“Pretty cool, eh?” Byakuya triumphed, hands on his hips. “They glow in the dark.”
Senku’s face remained completely unchanged. “Hmm. Kinda lame.”
“Oh.”
“Well… Now that I think about it, they probably could be even brighter if they were more energized. And if it was darker, obviously. Though I guess that depends on the phosphor. Strontium aluminate would be ten billion percent better, but I’m pretty sure those are zinc sulfide at best…” Senku twisted his pinky finger in his ear, unimpressed. “You bought the cheap ones, didn’t you?”
Wounded, Byakuya’s face fell cartoonishly flat. “Well…”
It was enough to draw a giggle out of his son.
“Nah, they’re good,” Senku grinned, kicking his feet as he looked up. “Just not even one millimeter as cool as looking through the telescope.”
“Yeah,” Byakuya agreed, taking a seat beside him and sharing his upward gaze. He understood— when it came to a love for space, Senku was a lot like him, after all. “But at least when you lie down every night they can remind you of where you’re headed. Though, knowing you, you hardly need some cheap plastic to keep your eyes on the stars.”
Senku was too lost in thought to see the twinkle in his old man’s eyes.
“Senku, I know you’ll…” Byakuya trailed off, aware that he’d gotten entirely too sentimental. “Ah, nevermind. I’m going to space, and then I’ll tell you all about it. So you’ll know what to expect when it’s your turn!”
“Nah,” Senku smirked. “I’m coming with.”
Byakuya would never tell Senku he was too young. “Of course you are.”
Determination and imagination stirred, and suddenly, the stars seemed to materialize around them. They were no longer in Senku’s bedroom—they were in space. Father and son; two astronauts that would surely be separated by time, but always gazing up at the same moon. Byakuya knew Senku would get there one day. He knew it better than anything. Ten billion percent.
“Well you’d better get training instead of waxing poetic over some cheap plastic stars. I’ve already heard enough pity parties about that swimming test.”
And just like that, the stars disappeared from Byakuya’s imagination.
“Stab your old man in the heart, why don’tcha…”
…
“You’re still awake, huh, Senku-chan?”
A quiet voice tears Senku from his memories.
“Yup.”
The observatory’s door latches shut, and the floor creaks as someone sits beside him. Senku would have immediately known who’d caught him reminiscing even without recognizing the voice. The bat bastard probably knows exactly what—or rather, who—Senku was reminiscing about. But Asagiri Gen always knows when to save face. And when to save someone else’s, too.
It’s deep into the night. The others had yawned their final ‘happy birthday’s and turned in a few hours ago. But Senku’s never been the type to go to bed at a reasonable time, and tonight is certainly no different. Staring through the telescope at the vast expanse of space has kept his mind busy. He’s even maneuvered it so that he can sit, wistfully admiring the stars.
He’s revisited a lot of memories tonight—the day he decided he’d go to space, time spent building rockets with Taiju, and of course, the countless hours he spent perched by his bedroom window, gazing through his telescope. He was bound to remember something like those glow-in-the-dark stars eventually. Not that the cheap plastic was what made that memory special.
“So,” Gen cuts through the silence, breath visible in the cold. “Did you have a nice birthday?”
Senku leans back on his hands and groans. “Well, dragging all those minerals back here was a huge pain in the ass. That’s for sure.”
“Well you can’t be as smart as you are and brawny,” Gen teases. “That’s like, totally unreasonable, you know.”
“Heh. Maybe.” Senku places a palm on the telescope, admiring it. “But it wasn’t bad. Not bad at all.”
Triumphant, Gen beams. The way the stars reflect in Senku’s shimmering eyes is mesmerizing, and as if acknowledging Gen’s staring, Senku scoots a little closer to him. It’s under the guise of moving the telescope, of course, but he really ought to know he can’t fool a mentalist.
Despite all of Senku’s posturing and skeptical diatribes on the subject of love—or anything even slightly vulnerable—he’s pretty easy to see through. And never in his life has Gen been so tempted to kiss someone on the cheek, just to see if he can get away with it. But current body language aside, he knows Senku probably really means it when he says he doesn’t have time for that kind of thing. Not right now at least. Maybe someday.
He makes a far less risky decision, leaning his head on Senku’s shoulder and trying not to blush. It’s remarkably telling that Senku doesn’t pull away. The fact that he leans into it is practically a marriage proposal, in fact. And although Gen may be an expert liar and manipulator, he can’t calm his racing heart even a little bit.
Meanwhile, Senku lets himself fully enjoy the moment and Gen’s warmth beside him—call his indulgence a birthday gift to himself. Maybe tomorrow he’ll invent some kind of logical excuse for the situation they’re in. For now, he’s content to share Gen’s company as sleep begins its nightly beckon.
“You did a good job with that telescope, mentalist.” His assessment is little more than a whisper.
Gen smiles fondly.
“You’ve been busy, but I know your heart still wants to reach space. I thought maybe you could use a reminder… Though knowing you, you hardly need some primitive, glorified magnifying glass to keep your eyes on the stars.”
Senku pulls away, face etched in surprise. But it quickly dissolves as he laughs under his breath.
“What??” Gen straightens, hair spiking like a spooked cat.
“Nothing, nothing.” Senku waves him off. “Call it déjà vu.”
It certainly doesn’t seem like nothing. Senku stares off into the distance, wearing an expression that Gen’s seen before. It’s the same unmistakable nostalgia that has only ever accompanied discussions about his dad.
Gen rests his head on Senku’s shoulder once more, finding it easier to do this time. With how much they need to get done tomorrow, he really should suggest they get some rest. But then Senku slides his hand closer, looping just his pinky over Gen’s, and time seems to slow.
They both decide it wouldn’t hurt to stay like this. Just for a little while.
Tomorrow they’ll move on like nothing happened, focus redirected to matters far more pressing. But for now, beneath stars that sparkle like crushed diamonds, the pair escape from their current reality to memories of the past and hopes for the future. Onward and upward.
Moments before Gen falls asleep against the warmth of Senku’s shoulder, he musters a gentle whisper. Glowing in the darkness.
“Happy birthday, Senku-chan.”