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The difficulty of having such an active mind is that even in the midst of a crucial mission to craft their way to the moon, defeat a mysterious enemy, and bring back humanity, Senku can’t resist undertaking side projects. Projects that, given his limited time during the day, he has no choice but to pursue while fighting bouts of insomnia, hauling himself into his lab to see what wonders he could concoct for this Stone World in a matter of hours.
Unfortunately, his enthusiasm doesn’t always outweigh his fatigue. It’s how he spills a slew of chemicals over himself while toying with what he could create by mixing them together. Rookie mistake, considering the toxins they contain and the corrosive effects they’ll have on his skin if he doesn’t wash up quickly.
He sighs, running his unsoiled hand through his hair irritably before cleaning up the spillage and resigning himself to trudge to the nearby lake. He uses the light emanating from the full moon to guide him on his path, tripping more than once on tree roots and stone fragments he hopes aren’t remains of humans that snapped off on his way.
The anomaly comes when he peeks into the clearing where the water glitters invitingly and discovers he is not alone.
Standing near the center of the small lake is Tsukasa, who appears to be lost in thought. Given his height, the entire upper-half of his body is exposed even when he’s so far out. His pale skin glistens under the moonlight; flawless, without a blemish in sight due to the healing properties of the petrification device. His wet hair is cascading over one shoulder, and he’s facing sideways from Senku’s direction, giving him a generous view of him in his entirety. He is reminiscent of a sculpture of some Greek God; a deity with a grand temple that would garner thousands of followers with one awe-inspiring display of his prowess. And while Senku has never been particularly compelled by fine arts or religion, the sight makes him stop and stare, heart caught somewhere in his throat.
Sensing eyes on him, Tsukasa turns so he is facing Senku properly. Senku watches as his expression melts from guarded skepticism to open affection as he registers who has interrupted him. Huh. Has Tsukasa… always looked at him like that, or is this a more recent development? For once, Senku doesn’t have the answer.
“Senku,” Tsukasa greets, his low voice wisping through the air like a melody. “What are you doing up at this hour?”
“I could ask you the same,” Senku says, already wearing a smirk. “You’re posed like some mythical being out to lure me to my death.”
The ghost of a smile dances on Tsukasa’s lips. “I doubt I have the same pull as a siren. Besides, I think I’ve done enough damage for one lifetime.”
Senku snorts, choosing to ignore the resentment in Tsukasa’s voice. “Alright, then let me guess. You’ve been pushing yourself to the limit with your over-the-top training regiment, since you’re still reluctant to surrender your position as the most overpowered beast in the Stone World.”
“And you?” Tsukasa asks. He gestures to the stains on Senku’s clothes. “Conducting late night experiments? Are the great advancements being made during the daylight not enough to satisfy your mind?”
“You should know by now that the scientific mind is never fully satisfied.”
Tsukasa hums. “Yes. I suppose you’ve proven that countless times, haven’t you?”
It’s ironic, really; in the past, it was the drive of their entire confrontation, but where old frustrations and incomprehension once lingered, only light-hearted teasing remains. Whatever grudge Tsukasa held—and perhaps, in some ways, still holds—against the world, it stopped applying to Senku long ago. It probably never truly did in the first place.
He’d count himself lucky, but luck has nothing to do with it.
“Obviously,” Senku agrees. “But as much as I’d love to dive into it, I didn’t come to chitchat.”
Tsukasa nods seriously as Senku removes his deerskin shoes and pouches. “I assume whatever chemicals you were handling were quite hazardous.”
“The results aren’t near as interesting if they’re not,” Senku muses, frowning down at his hand, which is pink from his failure to avoid rubbing at the irritated skin.
“You shouldn’t do anything risky without taking the proper safety precautions,” Tsukasa warns. “Or at least, consider having some supervision at night in case any accidents do occur.”
“What am I, some naïve little kid?”
“Even a skilled athlete would be foolish to attempt strenuous reps without a spotter. There’s no need to take unnecessary risks.”
Senku rubs at the inside of his ear. “You know, for such a contrarian, you can be a real stickler.”
Tsukasa’s smile is somewhat sheepish. “I don’t intend to fall short on my promise to keep you safe again. So next time, if you need a companion at night, don’t hesitate to find me.”
Senku scoffs, ignoring the gross, fuzzy sensation clawing at his chest. “A sleep-deprived fighter is the last thing I need.”
“Mm. Well, at least allow me to stay as you clean yourself up, in case any inflammation worsens.”
“Not like I was gonna kick you out. Pretty sure the lake’s big enough for the both of us,” Senku points out, though another strange itch is creeping up his spine, putting him on edge.
Tsukasa spares him from any pressure by turning his back on him, splashing water on his own skin in an obvious attempt to appear busy washing himself. It almost makes Senku laugh. Nudity isn’t anything to be ashamed of in a primitive world like this, he’s got an eyeful of Tsukasa’s junk more than once and he knows Tsukasa’s seen his as well. It’s nothing to act like a delicate maiden over.
So it’s illogical that relief flows through Senku as he is able to strip out of his remaining clothes in some form of privacy before dipping his toes into the lake. It’s moderately cold to the touch, enough that given his weak constitution, he’ll be shivering in no time. Rather than dragging out the inevitable, he slides his body down, submerging himself fully into the water. He dunks his head under to wet his hair, skin prickling with goosebumps at the harsh change in temperature.
He sputters on the way up, chills running up and down his body. “If this water were any colder, I’d probably contract hypothermia…”
At his muttered complaint, Tsukasa turns to look at him, offering a sympathetic smile. “It would probably be wise of you to move around then, to garner some extra body heat.”
“Yeah, yeah,” Senku says, arms wrapping around his torso as he wades deeper into the water. It reaches near his waist by the time he nears Tsukasa, and he’s only a little perturbed at how it makes their height difference all the more pronounced. Does this guy seriously have to be such a giant?
“Hey,” Tsukasa greets, staring down at Senku fondly.
“Hey,” Senku responds, gaze locked onto Tsukasa like he’s drawn to him via magnetic force. His voice sounds a little strange, probably shaky from the drop in his body temperature.
Tsukasa appears no less captivated, like Senku holds the answers to questions he’d never thought to ask. Between them, something fizzles, like a chemical reaction bubbling over before bursting into an explosion. Dangerous and tempting all at once.
Tsukasa extends a hand, fingers tickling near Senku’s temples and carefully tucking a piece of hair behind his ear. Every nerve in Senku’s body feels like it’s been set afire. “You look… different like this.”
Senku raises a skeptical brow. “Different how?”
There’s a little shake of Tsukasa’s head, like he’s at a loss. “You probably wouldn’t like any answer I have to give.”
“Try me,” Senku dares.
There is a pause, and Senku counts the seconds—1, 2, 3, 4—before Tsukasa answers.
“Undone. Beautiful.”
The words are so genuine that it catches Senku horrifically off-guard, his stomach dipping and his cheeks feeling very hot before he can fumble for his composure. He crosses his arms, trying to play it casual as he rolls his eyes, like he’s irritated. As if his heart isn’t thudding in his chest because of idiotically flirtatious words of all things.
“Yeah, well, don’t get used to it,” he mutters.
Tsukasa chuckles softly, his fingers moving to run through locks of Senku’s hair in an affectionate manner. “Your hair is growing quite long, you know. Soon, I doubt it will have the power to defy gravity as usual and will begin to wilt on its own. In fact, I believe it may have already been starting…”
It’s difficult to tell if Tsukasa is teasing him or not, so Senku merely scoffs. “It’s not some droopy plant. And I’ve been meaning to trim it, anyway.”
Tsukasa hums in understanding, finally removing his hand and taking the heat hovering near Senku’s cheek with it. Desperate to regain it, Senku makes a risky gambit of his own, pulling a lock of Tsukasa’s long brown hair into his hand. Tsukasa’s eyes go imperceptibly wider.
“Like you’re one to talk considering your crazy long hair,” Senku points out. “Actually, that’s one thing I’ve never got. I’m not gonna claim to be an expert in mixed martial arts, but I’d figure this style would be a disadvantage.”
“I can see how you’d come to that conclusion,” Tsukasa says. “But hair pulling was against regulation during my fighting days back in the old world, so it never posed much of a threat. Though I suppose in our current primitive world, such rules no longer apply.”
“So, why not cut it?”
“You seem awfully concerned,” Tsukasa says, and this time, Senku clearly hears the teasing lilt of his voice. “Is it not to your liking?”
Senku briefly entertains the idea of a Tsukasa with his hair chopped off, and nearly scrunches his nose in displeasure. While he’s no expert in aesthetics, Tsukasa’s current style fits him perfectly, its untamed beauty only making him more compelling. It would be a waste to alter it, like purposefully removing charm points or something.
“What’s it got to do with me?” he asks instead. “I’m only making an observation.”
“Hm. What indeed?” Tsukasa muses. “To answer you honestly, I simply like it this way. And in the event anyone gets close enough to take advantage of such a thing, they would sorely regret their actions.”
Senku smirks, and his other hand reaches up to dance through the strands of Tsukasa’s hair as well. Tsukasa’s breath quickens, and Senku has long forgotten he had ever been freezing.
“All I’m seeing is that the ‘Strongest Primate High Schooler’ has an exploitable weakness,” Senku taunts.
And if anyone knows the merits of taking advantage of each and every opportunity he is given, it’s Senku. Following an impulse he can’t ignore, his grip tightens on Tsukasa’s hair, and he yanks him down to his level, pressing a kiss against his lips. He holds it there like a question, much to Tsukasa’s bafflement.
Tsukasa has stiffened, not taking any action in turn for one second, two seconds, three seconds—but before Senku can pull back to allow him space, he clicks back into reality. Tsukasa leans down further, and his hands drop to rest low on Senku’s hips as he drags him closer. His lips begin to move against Senku’s and an electric current races through the entirety of Senku’s body as they fumble to find their perfect rhythm.
Under the prying spotlight of the moon, they become lost in the chase of passionate kisses—nips, smacks and satisfied hums drowning out the scuttle of the nearby forest.
When they part, Senku blinks dazedly. Tsukasa shifts from a blob to a defined form before his eyes, cheeks flushed and appearing every bit as mystical as he had when he’d spotted him, only now, Senku is certain he had signed his own death warrant.
His lips part and the first thing he blurts, embarrassingly, is, “I do like the hair.”
And Tsukasa snorts, expression contorting in surprise before he sinks into a full belly-laugh, curled over in a concoction of shock and glee—likely caused by the crazy output of neurotransmitters working overtime from constant turns of what the fuck, what the fuck, what the fuck.
Senku catalogues the image, along with each peal of laughter, and files it in some dusty corner of his mind where no one would think to look for it.
When Tsukasa settles, it is with a shake of his head and fond amusement. “I do hope you’re aware you’re the only one who could get away with a dirty trick like that.”
“I’m aware,” Senku says, because he’d seen time and time again, since they’d stood as allies against Hyoga—bleeding and desperate but united, that Tsukasa would follow where Senku leads him without question. “You’d better be careful, Tsukasa, or you’re gonna start making me feel like I’m special.”
“You are,” Tsukasa says, without hesitation. “You know you are.”
And Senku cannot fool himself for a moment into believing he means it in a general sense, like he’s considering the wider scope of what Senku has offered the world at large since his revival.
There’s no way he can verbalize any half-decent response to such a declaration, so he doesn’t. His fingers finally slip from locks of thick hair and settle high, one nudging Tsukasa’s cheek and the other curled around the back of his neck. He drags him in again, and when their lips crash together it is hungry, desperate, a frantic scramble that whispers, ‘you are, too, you are, too,’ into each shared breath.
When the sun rises tomorrow morning, reality will set back in—the hectic roll of task after task to return the world to some semblance of normalcy that leaves no room for detours. Still, Senku wonders if he asked, if Tsukasa would meet him in the woods again tomorrow night, and the night after that, and the one after that.
They pull apart only after the ferocity of their kisses has mellowed into something gentler, a series of soft drags of their mouths offering a warmth that spreads through Senku’s bones and eases him closer to Tsukasa’s bare chest.
And when their gazes flicker to land on one another, and Senku is greeted by a hurricane of steady devotion, he finds his answer.