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Gen liked Senku’s hands. Like, really liked his hands. There was something about them that turned him on like crazy. They were slender, just a bit bony with some veins showing through on the backs, and the leather wrappings he kept around his arms added a bit of sexiness Gen couldn't quite put his finger on. Time and time again, he’d find himself watching as Senku’s graceful hands worked, handed fragile instruments, performed delicate maneuvers. His eyes fixed on how Senku’s knuckles showed through so boldly when he flexed his hands, how gently his long fingers handled his equipment, and the way his muscular arms and neck complimented them.
Oh, how he wanted those hands to do terrible things to him.
He had spent countless nights fingering himself, wishing that it was Senku crouched over him, thrusting his fingers in and out of his dripping cunt. He found himself whispering "Senku-chan, Senku-chan, I’m coming" over and over during his orgasms. He couldn't get Senku's stupid idiot genius face out of his head. Whatever he was doing, he'd remember Senku, think about what he'd say if he was here right now, and Gen would scold himself, feeling his face heat up at the thought of his name. He wasn't sure about how Senku felt about him, which was incredibly frustrating since that was his job: to decipher what others are thinking. But no. There was something special about Senku that was impossible to see through, and it was irresistible to Gen. He could sit alone with Senku and talk for hours and it’d feel like a minute. every second he spent with him was just exhilarating, and his day was made every time Senku enlisted his help. He wanted more, though. A deeper connection. A more personal one. A more physical one.
***
"Hey, Senku-chan, can I ask you something?" Gen was laying on the grass-matted floor with his hands clasped behind his head. Senku sat at the table next to him, fiddling with some wires.
"Yeah?"
"What's your biggest sexual fantasy?"
They didn't tend to shy away from crude or inappropriate topics in their conversations. In this world, oversharing was basically unheard of. They'd had a few conversations about masturbation, who they thought was fucking who, et cetera before. Gen didn't really know what he was thinking or expecting when he asked, but he figured that given their history of long talks about all sorts of sexual things in the past that it'd be fine...
"Ah..." Senku didn't look up from his task, but he raised his eyebrow and a subtle smirk appeared on his lips. "That's a tough one."
"Right?" Gen was eager to hear Senku’s response. Please, God, let it be something I can offer to do for you.
"Well," Senku began, "I think I'd mostly just like to hold someone down and be able to have total control over them. Make them squirm and shit. I think having someone cute and smaller than me sit in my lap while I finger them and play with their tits would be hot. I also kinda like dry humping..." he trailed off, trying to think of anything else off the top of his head.
Gen swallowed. Oh, God. You're checking all my boxes here. You wanna hold someone down and rail them but also let them sit in your lap while you grind on them? Sign me the fuck up. I’ll be all of those for you. Whatever you want. Let me in.
"Really? That's kinda hot, I guess," he replied, trying his best to conceal his unbridled horniness at the thought of being held down and subject to Senku’s every will and desire.
"Pff. Yeah. Been too busy to really jack it lately. Kinda wish i had the time to do it, though. Too bad there’s no porn here.”
You're right here alone with me. Take me.
"Anyway," he continued, interrupted by a zapping noise from the machine he was tinkering with. "How about you?”
Gen sat up. Yes. Thank you for asking.
"Well," Gen looked Senku straight in the eyes, "My biggest one getting to sit in the lap of a guy taller than me while he fingers me and plays with my tits and grinds his cock up on me. Also a fan of being pinned down and violated by someone who will dirty-talk to me and really hammer into me who's boss. Bonus points if he has green hair and red eyes."
Senku dropped his soldering tool with a clatter. He stared Gen straight back.
"Are you doing what I think you're doing?"
Gen didn’t break eye contact.
"Absolutely."
Senku narrowed his eyes, a look of vaguely annoyed disbelief on his face.
"Are you serious?"
Gen smiled. "Yep. been thinking about it for years."
Senku placed his hands on the table and stood up, knocking some of his shit over in the process.
"You wanna get railed? ‘Cause this is how you get railed." His voice was hushed, but firm.
Gen could feel his heart racing and his palms growing sweaty, but he stood his ground.
"If you’re up to it. Do whatever you want to me. I'm yours." I'm yours.
Senku sneered and licked his lips. "You sure?"
"Please."
"Alright then."
Senku stepped over to Gen so that he was standing right above him. He gently pushed him back down with his foot so that he was laying on his back again. He crouched down over him and grabbed his upper arms to pin him down to the floor beneath him. Gen could feel his heavy breathing, above him, and when he looked down he saw Senku's erection beginning to poke through his tunic.
"Hmm... How should I start..."
Gen nervously smiled, deciding to take the plunge and ask.
"How 'bout you kiss me?"
Senku smiled. "’Kay." He slowly leaned down and gently pressed his lips to Gen's.
"Mmmm..."
Senku went deeper, coaxing Gen’s mouth open with his tongue.
"Hnn... Senku-chan..." He felt Senku smiling and what is that, even giggling into the kiss?
"W-what? What is it?" Gen asked defensively.
He chuckled. "Just thought our first time would go a little bit differently than this."
"Thought? You’ve thought about this before?"
Senku grinned, still sat on top of him, his arms by either side of Gen’s head, still trapping him under himself.
"'Course. I always thought you were kinda cute. Just didn't know how it'd go down.Thought it’d be a little more romantic."
"Really..." Gen affectionately crossed his legs over Senku’s body to pull him closer, now feeling more secure. Senku went down to kiss him more, gradually working his way up from light pecks on his mouth and cheeks, to something a little more intense to full-on making out. Gen moaned and whimpered into Senku’s mouth, as he was beginning to feel more and more comfortable. The feeling of Senku’s weight on top of him felt incredible. Gen hugged Senku tighter, closer to him, as close as he could, drinking in the warmth of his body. Senku abruptly pulled away, and leaned back up. He wiped his mouth with the back of his hand, panting.
"You're so adorable... Now let's get these clothes off you."
"Y-yes!" Senku guided Gen as he slipped off his overcoat and clumsily helped him untie the rope around his waist in order to get his yukata off. After Gen was just down to his pants and binder, Senku took a moment to admire the sight before him.
“Wow... amazing." he ran his fingers over Gen’s shoulders, feeling his sharp collarbones and caressing his neck and the backs of his hands. He sighed, repeating "amazing" several times in a whisper, causing Gen to get goosebumps all over his body.
"T-thank you..."
"Mhmm..." Senku answered as he pushed Gen’s bangs out of the way with his palm and gently kissed him on the forehead. They were both sitting up now, facing each other, with Gen’s legs still crossed around Senku’s waist.
"Now undress me."
"Yes, sir~" Gen skillfully undid all the fastenings on Senku’s shirt and eagerly pulled it open, exposing Senku’s chest.
"W-wow! I, I know I've seen it before, but to uh, be this close and personal with you like this–" Senku just smiled in response as he absentmindedly played with the fringe of Gen’s hair.
"Keep going. Don’t be shy."
"Okay..." Gen helped Senku get his arms out of the sleeves and moved his attention downward. his hands hovered over Senku’s clothed erection.
"Uhhh..."
Senku took Gen’s wrist in his hand and guided it closer down.
"Hey. Don't be shy. It’s just me."
"Haha, I guess... Um..."
He pulled down Senku’s skirt and watched in shock as his surprisingly massive cock sprang up. He could see Senku’s chest rising and falling as he began to breathe harder. He patted the top of Gen's head.
"Only you could ever get me this rock hard."
Gen blushed harder than he already was.
"Ahaha..." He took a moment to stare in both shock and delight at it, taking in as many details he could to use as spank bank material later, from the slight upward curve it had to the reddened tip to the veins going up and down the shaft.
"Now I'll finish you.." He undid the string keeping Gen's binder together and he watched in delight as his tits dropped down.
"Ah, I see you're pretty big too." Gen giggled shyly. Senku lifted his hands to his chest and looked back up to Gen for permission.
"May I?"
"Yes, please."
“Mm." Senku placed his hands over Gen’s breasts and began to gently knead them in his palms.
"So soft..." Gen looked down and saw those hands he that he had obsessed over for so long, and he felt a chill go down his spine. He stirred his hips so that his crotch grinded against the heel of his foot, desperate to get any sort of stimulation down there. Senku picked up his pace and groped Gen rougher and rougher, moving his hands faster and squeezing harder. Without taking his eyes off of Gen's breasts, he inched closer so that he was right up to him.
"So fucking good..." he whimpered, the sheer pleasure making his head cloudy. Senku abruptly stopped and moved back a bit.
"Hey. C’mere. Get up."
"Hm?" Gen sat up on his knees, though they were weak from all the excitement from before.
“Eek!”
Senku had moved behind Gen to grab him by his upper arms and drag him back a bit so that Senku was sat against the wall and Gen was sat between his legs, both of them facing forward.
"That's better." Senku rested his chin on Gen's shoulder from behind him and reached his arms around Gen’s body. He inquisitively ran his hands up and down Gen’s body.
"Uhh... Can you keep doing what you were doing? That felt like, really good."
"Sure, sweetheart."
Sweetheart? Did you just call me “sweetheart”? Gen wanted to squeal and fanboy and all that shit but he didn't want to embarrass himself in front of Senku more than he was already doing right now. Still, though... he could get behind that. Sweetheart…
His giddy little train of thought was stopped in its tracks by the sensation of Senku pinching his nipples.
"Ahh!"
Gen looked down and admired the sight of Senku’s perfect hands working on his nips. He reached back with one arm to run his fingers through Senku's hair and placed his other on his own so that he could feel those beautiful hands he had his sights set on for so long. He closed his eyes, took a deep breath, and savored the pleasure coursing from his chest to throughout his body. He listened to his heavy breathing beside him, and caressed his knuckles with his free hand. Senku took his hand into his own and squeezed it reassuringly. Gen could feel Senku’s hard cock rubbing onto him from behind, and in return he pushed his hips back onto it.
This is fucking amazing.
"You're being such a good boy for me," Senku cooed into his ear. "It was really cunning of you to ask such a bold question back there, mentalist." he chuckled, not pausing his massaging of Gen's tits for a second.
"Did you plan out that trick there? Huh? Did you plan on echoing whatever I would say to get into my pants? Hm?"
"Ah... A-actually, no... you-your—AH!" he was interrupted by Senku pinching his nipples particularly hard. "Your answer really did just... mmm... align with just what I'm into... a-and my strongest fantasies... I-I swear... hahhh..."
Senku kissed him on the cheek.
"S’what I thought. Good boy," he repeated. He lovingly ruffled Gen’s hair.
"Now let's get these off," he murmured, gesturing to Gen's pants. He stuck his thumbs into the waistband and pulled them down, coaxing Gen to curl his legs up towards him so that he could slip them off easier. He then tangled his legs with Gen's to keep them spread. He looked down over his shoulder at his cunt and saw that it had a very thick bush on it that, was in fact half-black and half-white, confirming his suspicions. He smirked to himself at the spectacle.
He moved his hands down, caressing Gen’s stomach as he made his way towards his pussy.
"Ready, sweetheart?"
"Yes, please go ahead..."
Senku carefully placed two of his fingers onto Gen's vulva.
"Wooooow... You're soooo wet," he murmured. "Makes me wonder how many other times you've gotten this wet while thinking of me, huh?"
He experimentally put a bit of pressure with his fingers onto his clit, causing Gen to whine and instinctively try to close his legs, but Senku kept them forced open.
"You like that?"
"Hnn... Keep going... Feels really good..."
"’Kay." Senku pressed down harder and began to rub his fingers over his cunt, occasionally teasing them over his hole.
"Aahh! Oh god! Faster!! Please! S-Senku-chan~!" Gen reached his arms back and grabbed his fingers into Senku’s hair. From behind him, Senku was rubbing his cock into his asscheeks, moving his hips in a steady circular motion. Gen pushed his hips back against him to help him out. Senku kissed his neck and tightened his grip around his body.
"Okay, I’m going in now."
"Mhmm," Gen replied nervously. He looked down at Senku sticking his first finger into his vagina, and felt him begin to rhythmically move it.
"That okay?"
"Yeah."
He sighed and settled back into Senku's embrace, melting into the wonderful feeling of being held by him. Senku teased in his middle finger, and then stuck it in all the way. His other hand had gone back up to fondle one of Gen's breasts, going between massaging it and pinching the nipple. Gen, moaning and panting, bucked his hips back and forth in response to the pleasure.
"Aah... Senku-chan! You're so good at this! Oh my god!" Senku just grunted in response and began to suck on the side of Gen’s neck as he stuck in his third finger. His pace of plunging his fingers in and out had quickened, and he started to move his fingers upward a bit to stimulate his clit more. "Mmmghh!!! Mm!! Ah! Senku-chan! Don't stop! Please don't stop!" Gen practically screamed.
"Don't worry sweetheart, I've got you," he breathed, speeding up even more as he fingered him as hard and as fast as he could while he desperately grinded his cock onto Gen’s ass, about to cum himself.
"FUCK! I'm gonna cum!! Ffuck!! Nngh, harder! Don’t stop!"
"Damn, he can be loud when he wants to," Senku remarked to himself. He briefly considered if anyone could hear them from up in the observatory, but even if they could, he didn't care. He moaned as he thrusted his cock between Gen’s asscheeks one final time and felt the orgasm course through his body, spilling his semen all over Gen’s back and his own stomach. He didn't stop rubbing Gen’s cunt, and he felt him begin to tense up in his arms as his own climax approached.
"FUCKFUCKFUCKFUCKimcomingimcomingimcomingIMCOMING," Gen babbled incoherently as he desperately bucked his hips, holding onto Senku for what seemed to be dear life. After a few seconds passed, they had both come down from their orgasms. Senku released Gen from the hold he had him in and they collapsed next to each other, not saying anything as they caught their breath.
Eventually, Senku rolled over on his side to face Gen and poked his nose.
"Hey." He ran his hands over Gen’s body.
"You alright?"
"Yeah," Gen quietly responded. Senku reached up to caress Gen’s face.
"You did really well," Senku praised. "You're so obedient. And sooo adorable. Feeling you squirm in my arms was incredible."
Gen giggled. He scooted closer to Senku and buried his face in his chest, sighing. Senku lovingly ran his fingers through his hair.
After a few minutes of quiet, he tugged at Gen’s arm.
"Hey. Let's go get cleaned up. Can’t have my boyfriend laying around all messy like this."
Gen shot his head up in shock.
"Boyfriend?"
"Huh? 'Course. Isn't that how it works? I wouldn't not want to be dating you after what just happened."
Gen hid his face in his hands.
"Yeah... uh... It’s just... It sounds so weird... boyfriend... but I mean… If you're okay with it... I wouldn't mind or whatever."
Senku smiled, lifted Gen’s chin up with his finger and kissed him on his forehead again. Gen’s face was bright red. Senku sat up, and patted the floor beside him. "C'mon. Get up. Let's go take a bath. Then we can go to bed."
"Okay!"
Senku stood up, threw his tunic on and as he was about to climb down the ladder, he looked back at Gen.
"Hey. I love you."
Gen's heart lept out of his chest.
"I-I love you too!! Always have and always will!" he stammered.
Senku grinned.
"So damn cute."
