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Very soon after meeting Kohaku, Senku had taken note of the Lioness’ utter disregard for closed doors—or privacy, for that matter. She’d happily climb through a window if she saw the need. So, when she appeared in the doorway of the hut he’d temporarily borrowed on Treasure Island, holding aside the draped fabric that passed for a front door, he didn’t even blink.
In the dim flicker of an oil torch, her eyes scanned his sweat-slicked face and bare torso, and he could tell the exact moment they landed on the wounds, two raw holes on his arm and shoulder, her eyes widening in horror.
“I’ll go get Francois,” she declared, already turning to leave.
“Kohaku.” His voice was firm, steady—concealing the effort it took him to stand from the low bed of palm leaves—. It had to be. He couldn’t afford the scene that would follow if she went waking the others. And besides… it wasn’t that bad.
She didn’t move, at least willing to listen to what he had to say.
“You’d be ten billion times more useful if you brought me the sulfa drug instead,” he said. “It’s in the lab car. Remember the jar from when we treated Ruri?”
There was a moment of hesitation before she turned slightly, reluctant.
“I do.”
The corners of his mouth lifted.
“Good. I already got everything else I need here, so don’t wake the others.” When she didn’t respond, he added gently, “It’s been a long day.”
She hovered, clearly torn.
Of course she was. Kohaku’s instinct to protect could overrule any command. But there was trust in him—strong enough for her to pause and weigh his words, even if it went against her gut.
Finally, she let out a sigh—bordering on dramatic—but at least the warrior faced him fully.
“On two conditions: first, I’ll stay here to make sure you really have this under control. Second, if you still look like…” she gave him a pointed once-over, frowning, “this by morning, I’m calling for help.”
Senku smirked. Given the limited information Kohaku had, that was the most logical course of action—something that he would’ve proposed himself if he had deemed it necessary.
“Deal,” he said.
Kohaku nodded and, just like that, she was gone.
In the silence that followed, he could hear his own heartbeat thudding in his temples. Exhausted, he sank back down. Though he normally welcomed some peace and quiet, tonight—with a fever fogging his mind and his skin hot and tight—the silence made him feel too aware. Of his own limits. Of the fact that he’d pushed himself too hard.
He let out a heavy sigh, picked up his Adson forceps, and braced himself to resume debriding his wounds. If only he’d reinvented local anesthesia by now.
The pain was immediate, sharp. He gritted his teeth as he worked, peeling away unhealthy tissue. Nothing critical—yet. No signs of foreign bodies, and the infection hadn’t gone deep. He’d caught it in time. But damn, it hurt. Thankfully, he could already see the end of it.
A slip of his forceps tore skin right then, sending a bolt of white-hot pain through him. He hissed, curling in on himself instinctively. The most irrational part of his brain screamed for him to stop everything and call it a day. He entertained the idea as he heaved and trembled silently beneath the weariness of the late hours, but a pair of hands steadied him gently, coaxing him upright.
“Just a... moment...” he managed, forehead resting on the shoulder in front of him. Kohaku’s shoulder. Her hand found the back of his neck—warm and grounding—and rubbed slow circles there. The motion brought forth the memory of their recent hug, along with a sense of comfort.
A couple minutes went by before her hand came to a complete stop.
“Have you been doing this every day, by yourself?” she asked, voice tainted with worry, though barely above a whisper.
Senku stifled a shudder and gathered the energy to pull away and meet her eyes.
“Nah. First time debriding my own wounds. Survival series made it look easier than it is,” he joked.
Kohaku furrowed her brows—either at the unfamiliar terms he used or at his obvious attempt to brush past the tension of the moment—but nodded anyway. Carefully, she let go of him and raised a small glass jar to his eye level.
“Is this the one?”
“Yep, just set it there,” he said, gesturing vaguely toward his first aid kit. He turned his attention back to the wound, pushing through the pain. If he kept moving, he could do this.
“I also brought a pot of water. Boiled,” Kohaku said, clearly proud she could apply some of the knowledge he had imparted on germs and disinfection.
He cracked a smile at that. A real one.
Yeah—he could definitely do this now.
“Are your hands clean?” he asked.
“Yes, I washed them thoroughly.”
“Perfect. I’m gonna clean up this mess, you’ll do the patching.”
She nodded without hesitation, moving to sit beside him.
“May I ask how this happened?” she asked, taking the gauze from his hand and dampening it before offering it back.
Senku met her eyes. Her tone was light—almost casual—but the weight behind her gaze said otherwise. No use deflecting. Given time, he was certain she could figure it out herself anyway.
“Ibara,” he stated flatly and her expression darkened like a storm rolling over. “He’s a stone statue now,” Senku was quick to remind her.
“…I know.”
She exhaled a tight, frustrated breath.
They fell silent as Senku focused on cleaning around his wounds, though, even without looking, he could feel the intensity of Kohaku’s eyes on him. His hands moved with practiced precision, but slower now, his energy visibly waning and the dull throb in his shoulder had settled into something deeper. He moistened one last piece of fabric to give his skin a final sweep. Done.
When he faced her again, he didn’t find the sharp glare he’d half expected. Instead, Kohaku’s expression was soft—almost contemplative—gaze fixed on his wounds. The moment their eyes met, she straightened, as if caught off guard.
“What?” he asked, raising an eyebrow.
“I just— I know you’re too stubborn to die, but… I’m still relieved.”
She smiled then—genuine, unguarded, and impossibly radiant. And for some reason, his thoughts stalled for a full two-point-seven seconds as he could only stare and register the relaxed curve of her lips, the soft shade of pink on her cheeks, the way her eyes crinkled just slightly.
He glanced away reflexively, reaching for a bandage to pass into her hands.
“Heh. Less talk and more keeping-me-alive then.”
Kohaku scoffed, rolling her eyes. “Please, you’re not going to die from this now.”
He chuckled.
Senku stirred.
Through closed eyelids he sensed the telltale reddish of a soft source of light—his desk lamp, probably. He’d been dreaming, and it wasn’t the pleasant kind. Muddled images, but a clear, raw sense of loss.
A gentle touch brushed his hair away from his face and settled on his forehead.
Right—he had a fever. Byakuya had forced him to stay home.
“Dad…?” he muttered. “What time is it?”
The hand twitched, then relaxed.
“I’m— it’s just me. Kohaku.”
His eyes fluttered open and he stared curiously at the slim figure kneeling beside him, his gaze drawn by the unusual teal of her irises, calm and soothing—it reminded him of the gentle sway of the ocean on a quiet spring day.
He blinked, thrown off by a sudden wave of familiarity washing over him, like the unsettling feeling that hits when you realize you're dreaming.
Reality rushed back in as if conjured at that moment.
The beam, the counting, the war, the sea, the Medusa... Kohaku.
“...Right.”
She offered him a smile, though there was tension on her eyebrows.
“It’s still night time, I’d say a couple hours before dawn,” she said, placing her free hand over her own forehead. “You were moving so much it made me worry, but the fever is down.”
“The sulfa drug is doing its job.”
Kohaku nodded, setting both of her hands on her knees, and Senku’s gaze followed the motion without thinking.
Something in his chest tightened—a foolish longing for the weight of a hand lingering long past the need to check for a fever, grounding him until he drifted back to sleep.
It had been literal millennia and he’d been a child then—still in the need of reassurance, still someone who accepted comfort without questioning it. Now he was a scientist with a world to rebuild, and sentimentalities had no place in the equation. He didn’t need reassurance when he had reason to tell him everything was under control.
And yet—somewhere beneath the tired logic, the longing remained, stubborn and unscientific.
“Senku?” Kohaku’s voice was quiet. Not just soft—uncertain. She raised a hand, paused midair. “Do you—should I…?”
He blinked at her. Then at the hand. She was asking if he’d want it back—her hand on his forehead. By now, he should be used to how well she could read him—she was perceptive on another level—but she still manages to catch him off guard at times.
So he thought about lying.
Then he thought about Byakuya again.
He glanced away, watching the flickering light cast dancing shadows on the walls.
“He used to do that—my dad,” he said with a faint smile. “He would stay with me when I was sick… Just sat there, all night, hand on my forehead like it was doing something.”
There was a breath of acknowledgement.
“Did you dislike that?” she asked after another beat of silence.
He hummed, noncommittal. “I said I did, but…”
Kohaku’s hand hovered in the air between them for a moment longer, caught in the silence of hesitation, before she finally withdrew it with a subtle, almost resigned motion.
“You are such a difficult man,” she sighed with an exasperated fondness that made his mouth twitch into something close to a genuine smile.
“Don’t you mean logical?” he countered lightly.
“I mean what I said,” Kohaku shot back, voice touched with a smile, before tilting her head towards the empty space beside him. “Scoot over. You seem well enough, so I’ll get some sleep too.”
“Fine by me,” Senku said, shifting onto his uninjured side, careful and slow. “Still gonna need you in top condition for ship repairs in a few hours.”
“Ha, of course,” she muttered and reached to turn off the oil lamp, wrapping them in the soft shade of the night.
He felt her warmth almost instantly as she lay down behind him, not quite touching, but close enough for a quiet comfort to settle between them. Senku let himself lean into it—not physically—but in that last loose stretch of thought where sleep dulled the edges of reason.
There, an absurd notion slipped into his mind.
Her existence was a rising tide, slowly reaching higher around him with each gentle wave—a quiet give and a patient take, asking for nothing he wasn’t ready to offer. At any point he could step back, turn away, yet he stays—to bask in the comfort of something he could rely on—the inevitability of her.
Maybe someday, he would allow himself to dive in, if only to see where the current might lead.
Not tonight, though.
Tonight, he was just tired and aching, and her presence was enough.
“Goodnight, Kohaku,” he mumbled, barely above a breath.
“Goodnight, Senku,” she whispered back, though he was already lost in the soft embrace of sleep, and this time, there were no sharp edges or restless thoughts to disrupt his mind.