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“Senku-chan?”
Gen’s voice rang out like a bell in the chilly silence of the observatory. Usually he just took his place next to Senku, like it was the most natural thing in the world, but tonight, something was… weird. Yeah, it was weird that Senku was just sitting there, gazing up at the stars, not even through his telescope, but Gen could’ve brushed that off. Senku didn’t acknowledge him at all, though; no snarky comment, no weird, random science fact. He didn’t even turn around when Gen said his name the first two times. The most damning thing, though, was something Gen couldn’t really put into words. The air just seemed… off. Colder than usual. Sharp, almost.
Senku had finally turned around, though, looking more than a little flustered, so Gen put on his best face and took his place next to him like nothing had happened. “The stars are pretty tonight, hm?”
Senku looked at him like he had said something totally out of the blue instead of a rational and relevant observation of their surroundings. Weird. “Yeah, I guess so.”
He allowed them to lapse into thoughtful silence again, and when the air turned serene again, became softer, Gen made his move. Allowing someone to let their guard down, allowing them to think they got off the hook, and then ambushing them immediately after usually made them more disoriented from their rapidly changing emotions, and thus more susceptible to letting the truth slip. “What were you thinking about, Senku-chan?”
The boy beside him stilled, the final nail in the coffin. Yes, he was definitely thinking about something before Gen showed up. “What do you mean?”
Gen’s lips curled into a sly grin. “You didn’t hear me the first two times I said your name, Senku-chan. What’s going on in that head of yours?” He cocked his head innocently, bringing himself a little further into Senku’s line of vision. He would not allow his presence to be ignored.
Senku dutifully avoided looking at Gen, training his eyes on the floorboards. He’d have to teach Senku how to properly lie sometime, he was going to get himself killed if he didn’t figure it out soon. He remained silent, though, which was especially uncharacteristic - Senku was always brimming with new ideas and thoughts, or at least with a witty comment or crazed mumblings or something, anything. Senku was a being that Gen couldn't contain if he tried, if he wanted to. New territory. Tread lightly.
“Thinking about the future, perhaps? Maybe making some mental war plans…” Gen mused thoughtfully, noting the way Senku relaxed slightly, like he managed to throw Gen off his trail. Unfortunately for the poor scientist, that in itself was a tell. Gotcha. “Oh, or maybe you’re thinking about the past, hm?”
Immediately, “No.”
“You’re an awful liar, Senku-chan.”
In a flash of movement, Senku whipped around to stare straight at Gen. Their eyes met in a fiery glare, locked in a quiet battle of which the outcome was determined before it even began. They knew where this would end, and it was up to Senku, the logical, efficient person he was, to stop wasting resources and delaying the inevitable.
He averted his gaze again and drew his knees up to his chest. It was new - Gen had never seen Senku look this… small before. It served as a stark reminder that at the end of the day, they were both still essentially kids. It made his stomach turn.
“I’m…” Senku’s quiet voice pulled him from his thoughts. “I’m thinking about my dad.”
It made sense - Senku had discovered Byakuya’s parting words recently. His words, Lillian’s song, the knowledge that they were really gone, it all weighed heavily on Gen. The hopelessness and finality that had been coursing through him - it probably didn't even touch what Senku was going through.
Gen nodded softly, inching imperceptibly closer to his friend. “What about him, Senku?”
He watched Senku’s eyebrows knit together again, words clearly bouncing around his brain, yet he made no move to voice them. Maybe he needed a nudge in the right direction. “You don’t have to tell me if you don’t want to, Senku-chan… of course, then you’d have to suffer through my lecture on bottling up your feelings.” He shot him a teasing smile, lifting the atmosphere just so.
Senku snorted and grinned back. “There’s really no winning with you, huh?”
“Nope~ I could even throw in a bonus speech about the power of friendship!”
Amusement danced in Senku’s eyes, giving Gen butterflies that he immediately decided to ignore. Processing those feelings was off the table. The teasing smugness in Senku’s voice didn’t help. “A speech on the power of friendship? From the self-proclaimed ‘shallowest man on earth’? How would that work?”
Gen gave a theatrical gasp. “Why wouldn't it work? Of course I’d need to know about that! Do you know how easily friendship can be exploited?”
Laughter was bubbling between them now. Their previous conversation hadn’t been forgotten, not entirely, but the anxiety embodied in it had dissipated. It was still just them - just Senku and Gen. Just like it always was. Senku gave him a playful shove and giggled (a sound that Gen now, after hearing it for the first time, was decidedly addicted to and would spend the rest of his life chasing). “God, you’re such a dick sometimes.”
“This has been established, Senku-chan, please keep up.” Their laughter simmered to a stop, leaving them in silence yet again and bringing their previous conversation back to the foreground. Neither of them was in a hurry - they really could stay here all night if they wanted, or just have this conversation another time. Gen was content with the progress they’d made, and Senku seemed like he was in a better mood anyway, so Gen was quite alright with shifting back to their regular stargazing and sarcasm, but Senku surprised him yet again.
“I wish I had told him more how much he meant to me,” Senku’s voice cut through the crisp air, like the sharp thunk of a dart hitting a bullseye. He looked unsure of himself, like he almost couldn't believe that he just said that. Gen watched carefully, not wanting to interrupt now that Senku had started. He shifted closer again. “I- I’ve never been the sentimental type… but I think maybe he wished I was. Sappy old man, heh.” Senku’s joking couldn’t hide the way his voice suddenly thickened, no matter how much he wanted it to.
Still, bravely, he continued. “He did so much for me, y’know? He sold his car when I was younger so he could buy me an actual lab. He never looked down on me, or treated me like a sob story or anything, and now I just-“ His tears were flowing freely now, like a dam that had finally, finally broken, but he made no move to stop them or wipe them away. Senku had gone completely rigid, frozen in the face of his feelings. “What if- what if he didn’t know? ” Senku finally choked out, his voice twined with a note of desperation that felt like a punch to the gut. He couldn’t stop himself from finally closing the distance between them and pulling Senku to him, tucking him face into his chest and wrapping his arms around the other boy like a vice. At first he was sure that Senku would pull away and chastise him, putting a stop to the moment right then and there, but then he felt hands come up to clutch his coat and pull them even closer. Senku was crying into his chest now; his hoarse, clipped gasps were somehow suffocating despite being relatively quiet in the open air of the observatory.
This was what Gen wanted, right? He wanted Senku to be open with his feelings, of course, but now… now that he was seeing the full extent of it, feeling the raw anguish that Senku had been carrying, all he could think was just how much it hurt. It hurt and he hated that these emotions had taken hold inside Senku, hated that there was anything that gave him reason to feel like this in the first place, hated that Senku had been bearing this weight alone. Naturally, his first impulse was to talk his way out of it - to reassure Senku or reason with him or even just make a stupid joke, but deep down, he knew that wasn’t what Senku needed right now. As uncomfortable as it was, he needed to let out everything he had been holding back in the face of the apocalypse and a war and a ridiculous personal responsibility to seven billion people.
So Gen made himself comfortable and with careful, practiced restraint, allowed all the tears of the last 3,700 years to seep into his chest. He carded his fingers through Senku’s hair, his other hand rubbing small, soothing circles in Senku’s back. The dull ache in his chest wasn’t gone, per se, but Gen always had a talent for turning his emotions off when there were more important things to worry about. He’d deal with it later; for now, Senku, his co-conspirator, his scientist, his best friend, needed someone to hold him and get him through his pain. There was no room in his mind for anything else.
Senku's sobs were dampened slightly, like he was still trying to reign them in and stop himself from hurtling over an edge he had fallen off of long ago. Stupid Senku and his ridiculous need to be strong all the time... it was going to be the death of Gen. They didn't try to say anything else (not that Senku would've been able to keep conversation through the tears) but that was alright; they said all he needed to. Gen didn't need a therapy session or a confession of all of Senku's most secret thoughts and regrets - he needed him to just feel. At least for tonight.
Eventually, Senku quieted completely and the flood of tears stopped, leaving only slow, even breaths in their wake. They parted without a word and Gen got up to prepare the observatory for bed. He closed the hatch, spread out their bedrolls, and arranged a pitcher of water nearby. He rummaged around his sleeves and- ah, yes he had a small pack of dried meat, full of the salt that Senku needed after all that crying. Silently, he handed the pack and a cup of water over to the other boy, not needing to tell him what they were for, and Senku obediently munched on them while Gen finished cleaning up. When they finally crawled into bed together after a long, emotional night, Senku faced diligently away from him, hiding his puffy, reddened eyes and his tear-stained cheeks. He’s embarrassed, Gen’s mind supplied, and of course he was. The last time he was that open and vulnerable in front of another person was… never, probably. The hesitation was understandable, really - Gen knew he gave off a certain ruthlessness, like he was constantly watching and categorizing any potential weakness (he was). But…
He scooted up right behind Senku, pressing his chest into his back and wrapping one arm around his stomach. He felt Senku’s breath catch. “Y’know, for what it’s worth… I think he knew,” Gen whispered into his back. “Your methods can sometimes be unconventional, sure, but you go to some pretty crazy lengths to look after the people you love.” He could just barely see Senku’s pink-tipped ears over his hunched shoulders. Cute. Gen let out a huff of laughter. “I bet you think you’re a pillar of stoicism and logic, but you’re pretty easy to read, Senku-chan.” At that, the air changed completely, giving way to what should’ve been their regular dynamic, but as Senku quickly flipped around so that their matching grins were mere inches from each other, Gen was faced with a newfound confidence from the other boy.
“Yeah?” Senku breathed, challenging. Gen could feel his warm breath on his face. The separation between them diminished with each passing day, it was torture. He wondered briefly when it would finally disappear altogether. “I thought I was being pretty subtle.”
It was at that moment that Gen became acutely aware of his arm, which was still resting on Senku’s hip. It was only a couple square inches of contact, still separated by layers of clothing, even, but it felt electric. He willed himself to calm down and contain his flush - he refused to be the first to break. “Sorry to burst your bubble, Senku-chan, but you’re about as subtle as the apocalypse.”
Senku barked out a laugh before flipping back around and settling back into Gen’s embrace. They would talk about it eventually of course, but for right now, they basked in the comfort that came with just being in each other’s presence, the simple understanding that they shared. “You’re not as subtle as you think either, mentalist.”
Gen couldn’t stop the giddy smile curling on his face, at the way Senku just got him. The differences between them were stark and blatant, but key underlying similarities threaded them together unshakably. They occupied the same wavelength, just different frequencies. “I’m choosing to ignore that. My control over my emotions is perfect and unwavering.”
“God, can you stop gloating for one minute?” Although he couldn’t see it, something in him knew that Senku was rolling his eyes at him. It was offset by the smile in his voice, which rang out loud and clear.
“No can do, Senku-chan~ I’m a prideful creature by nature. Oh! Before I forget, I really need to teach you how to lie sometime.”
“Now why would you give me that ability?”
“Ah, you might be right there, Senku-chan. It’s kind of cute to see you be bad at something for once.”
“...shut up and go to sleep, mentalist.”
Gen tucked his smile away in the crook of Senku’s neck and shoulder. The space they had built together was foolproof, infallible. It was a sense of security that neither of them had felt in quite a long time. “Whatever you say.” And finally, they slept.