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Sideswipe absently registers his brother’s presence in the doorway, mostly focused on carefully pouring energon batter into baking cups. There are four different flavors, each a different color, that he wants to try layering. Even if the gels don’t taste good, they’ll at least look pretty.
“Sideswipe?” Sunstreaker ventures.
“Mm? Whatcha need, Sunny?”
“Can I ask you a question?”
In the back of his processor, Sideswipe notes Sunstreaker sounds hesitant. But it’s not a complete novelty; Sunstreaker doesn’t like asking for anything. He likes to be self-sufficient, as if snubbing his nose at Primus for making them dependent on one another for their very lives.
“You already did,” Sideswipe says. His lips quirk upwards at Sunstreaker’s huff.
“Sideswipe, I’m serious!” The scuff of pedesteps indicates Sunstreaker takes a step into the room.
Sideswipe waves a hand behind him, nodding. “Alright, alright, I’m listening. What’s the question?”
He’s done another four cups before he realizes Sunstreaker hasn’t spoken. “Sunny? You still there?”
“Yeah. I just – ”
Sideswipe frowns at a drop of batter dripping down a cup’s side. He starts to wipe it away when Sunstreaker apparently finds the courage to finish his thought.
“Would you let me spike you?”
It takes a second for the question to register. When it does, it startles Sideswipe so badly that he drops the bowl onto the counter. The bowl clips the end of the tray of baking cups, which then spins and tilts dangerously over the side of the counter. Sideswipe fumbles to catch the tray and, instead of gripping it, ends up flipping it into the air.
Batter flies everywhere, most of it splattering on Sideswipe’s chest and face. When he tries to shield his head, his elbow catches the edge of the bowl and sends it sliding off the counter to slam onto the floor. More batter splashes up across Sideswipe’s pedes and shinguards. He remains huddled in on himself until the ringing of the metal bowl against the floor fades away. Then he slowly straightens and turns to face his twin.
Sunstreaker stares at him in astonishment and creeping horror. Sunstreaker’s not a fan of messes, particularly involving fluids. It’s one of the main reasons he doesn’t like to interface. That and the very well-known fact that he doesn't experience any sexual attraction. To anyone, even Sideswipe, Sunstreaker’s own bondmate.
“Uhh... “ Sideswipe trails off, at a loss for words.
“So... is that a ‘no’?” Sunstreaker says slowly, optics following the trail of warm batter down Sunstreaker’s left arm.
“I’m sorry.” Sideswipe’s voice is faint. “Can you repeat the question?”
Sunstreaker backs up a step, now looking more nervous than disgusted. “I – never mind, it’s...” He shakes his head and shifts as if about to bolt.
If he does, Sideswipe will have to give chase, and then the apartment will be a mess. “Sunstreaker, wait – did you ask if it would be okay if you spiked me?” Sideswipe pushes aside the shock, trying to sound calm and collected. It’s difficult when he feels warm, gooey energon batter seeping under his plating. But he does his best.
Sunstreaker ducks his head and bites his lower lip. “... yes?”
Sideswipe nods slowly, still confused. “That’s what I thought. What made you ask?”
“You don’t want to?” Sunstreaker’s head shoots up.
“Bro – have you met me?” Sideswipe looks incredulously at his twin. “I would love it if you spiked me. But you would hate it!" Sideswipe feels his tanks sink when he sees Sunstreaker’s shoulders tense. Yup – and there goes the stubborn tightening of Sunstreaker’s jaw.
“You don’t know that. I want to,” Sunstreaker announces. He glares as if Sideswipe’s sexual awakening and Sunstreaker’s distinct lack of one hadn’t almost caused a rift between them before they understood what was happening.
Sideswipe’s mouth moves soundlessly for several moments before actual noise comes out. “Sunny – I think it’s a really bad idea,” Sideswipe says slowly. His interface array vehemently disagrees, but his spark and processor know best on this one.
“Well, it’s not like I’m asking you to frag me – I’d be the one in control – right?” Sunstreaker confirms.
“Yeah, technically, but – ”
“You keep encouraging me to try new things,” Sunstreaker triumphantly adds.
Sideswipe gapes at his twin. “I want you to come out with me to the bar, not potentially scar you for life!”
“I’m not going to be scarred for life from a simple frag,” Sunstreaker says, tone dismissive. “It’s either yes or no, Sideswipe!”
“And if I say no?” Sideswipe can’t believe his brother is serious. Where had this even come from? Sideswipe frantically scans his recent memories, but he can’t find any in which he had indicated he wanted this.
“I’ll find someone else,” Sunstreaker retorts.
The reply is fast, too fast. As if Sunstreaker is 100% committed to this insane venture. “No, you will not,” Sideswipe spits out. He strides forward and flings his arms around Sunstreaker. His twin makes a wordless protest, but Sideswipe merely hugs him tighter. “I’ll do it,” Sideswipe whispers frantically. “Don’t go to anyone else. Promise?”
Sunstreaker is stiff within Sideswipe’s embrace, and he can feel their sparks thumping madly behind their chestplates. Sideswipe isn’t completely sure what has Sunstreaker’s going so fast, but Sideswipe knows his elevated rate is due to the fear of what could happen to his twin with someone else.
“Yeah, I promise,” Sunstreaker finally mutters. “You’re filthy. Can you let me go?”
Sideswipe smiles weakly against the side of his brother’s neck and purposefully rubs against Sunstreaker. “Get used to it, bro. ‘Facing isn’t exactly a clean endeavor.”
Step One.
“Training time!” Sideswipe announces as he enters their berthroom.
Sunstreaker looks up from his sketchpad and raises an optic ridge. “Training for what?”
“Interfacing. You have no idea what you’re doing, right? So, I’ll teach you!”
Sunstreaker does not look as impressed as Sideswipe thought he would. Sunstreaker wrinkles his nasal ridge. “Aren’t there instructional videos on this sort of thing?”
Sideswipe takes a running start and leaps onto the bed. Sunstreaker bounces a little and glares. Sideswipe ignores it with a lifetime of practice. "Maybe. But that’s boring. Besides, I thought it would be better to gradually work your way up to it. You have some pretty big hang-ups about sex, Sunny,” Sideswipe replies. He doesn’t say it to be mean, but it’s the truth.
Predictably, Sunstreaker bristles, because sometimes the truth hurts. “Like what?” he snaps.
“Oh, I don’t know. Maybe the whole hating to watch valve penetration?” Sideswipe says, tone challenging.
Sunstreaker’s lips thin. “I’ll close my optics.”
“So, you’re going to just nudge around with your spike until it slides in?” Sideswipe retorts. “That’s fine for fingering, but not for when you’re spiking me. C’mon, you trust me, right?”
Sunstreaker tilts his head as if considering it. Then he rolls his optics and tosses the datapad onto the nearby table. “Fine. All right. What do you have in mind?”
Sideswipe twists and falls onto his back, arms and legs akimbo. “Assume the position!”
Sunstreaker stares down at him, Not Amused. Sideswipe thinks he may get a lot of that expression over the next couple of days. “What are you talking about?”
“I’ve been thinking about the best position to be in when it’s actually time and... ” Sideswipe says.
Sunstreaker interrupts. “When will it actually be time?”
“Not for a while. Don’t worry, we have plenty of opportunities to practice.”
“No, I mean – why not tonight? Or tomorrow?”
Sideswipe snorts. “Right.”
As soon as he says it, he sees the thundercloud forming on his twin’s faceplates. Sideswipe rushes to explain. “Go ahead – pop your panel – but your spike’s not going to do anything, and you know it,” Sideswipe says. “You’re not sexually attracted to me, and we just bled off your residual daily charge yesterday morning. Plus, manual stimulation makes you twitchy so – “
Sunstreaker looks down at his lap and then sighs. “I see your point. So, no more bleeding off charge?”
“Nope. If you feel the itch and aren’t ready, we can. But we shouldn’t for the next few days to build it up.”
“All right. You were saying about positions?”
“Right! There are like a hundred positions, but the majority aren’t for beginners. I doubt you’d hurt me, but a newbie should watch their partner’s expressions for signs of pain anyway. So, missionary!”
Sunstreaker’s forehelm furrows. “Missionary?”
“Yup! I’ll show you.” Sideswipe flops back down, holding out his arms and spreading his thighs. “Come on in!”
Sunstreaker sighs – Sideswipe wears Sunstreaker’s vents are going to fail at this point – but rolls to his hands and knees and hovers over Sideswipe. The sight of his looming twin makes Sideswipe’s valve excitedly tingle. He sternly tells it to behave.
“What am I doing exactly?” Sunstreaker mutters, looking uncertain.
Sideswipe reaches up and places his hands on his twin’s hips. “Pelvis to pelvis, chest to chest. We’ll start with that, okay?”
Sunstreaker lowers himself the rest of the way down, carefully placing his full weight atop Sideswipe. “Like this?”
“Yup. Okay, now I’m going to spread my legs a little farther – there. See how things line up?” More of Sunstreaker’s weight settles between Sideswipe’s thighs. He automatically brings his knees up, bracketing Sunstreaker’s waist. “Now, to get leverage for thrusting, it helps to elevate your upper body, so put some of your weight on your palms or forearms."
Sunstreaker props himself up and gazes at Sideswipe from inches away. Sideswipe’s spark beats faster at the way his twin’s body fits so well between Sideswipe’s legs. "Yeah, like that. Um, perfect," Sideswipe says, voice a little weak. He continues after clearing his intake. “Okay, for the thrusting – you’ll be distributing your weight kinda evenly between your arms and your knees. You may need to spread your legs just a smidge – “
“Like this?”
Sunstreaker’s getting into it now, with the clinical curiosity he shows when Sideswipe walks him through something about interfacing. It was the same way when Sunstreaker learned to finger Sideswipe. Of course, Sunstreaker has never been in this position before. Nor has his panel been grinding so deliciously against Sideswipe’s. Then Sunstreaker shifts, withdraws slightly, and moves in a mock thrust. “Is this right?”
“Uh-huh,” Sideswipe says. His voice is faint, and his vision fritzes a little at the edges.
Sunstreaker looks up from where he had been peering down the length of their bodies, trying to see where their groins meet. He sighs when he sees Sideswipe’s expression. “You’re going to have to self-service before we recharge tonight, aren’t you?” Sunstreaker’s tone is matter-of-fact.
“ – maybe?”
Step Two.
“All righty, we’re working on penetration tonight!”
Sideswipe walks backward into their berthroom, holding Sunstreaker by the hands. He isn’t quite dragging his twin, but Sideswipe’s certainly pulling. Sunstreaker’s wearing his Not Excited expression. It’s not the ‘Oh, please, Primus, no, Sideswipe’ face, but it’s close. Well, tough energoncookies. Sunstreaker is the one who keeps insisting they do this.
“And how exactly are we going to do that?” Sunstreaker comes to a stop in front of the berth as Sideswipe releases him to climb on.
“So, I figure, you don’t have to like the sight of penetration. You just have to tolerate it enough to make sure your spike goes in the right hole,” Sideswipe says.
Sunstreaker looks horrified and a little queasy. “Could I really... ?”
Sideswipe waves him to a stop. “Let’s not. We’ve already established it’s no fun for either of us if you blindly poke around, okay?”
Sunstreaker reluctantly nods. “I’ve fingered you before. Are you – are you going to make me watch myself do that?”
“Sunny – ” Sideswipe holds out a hand, and Sunstreaker takes it. “I’m not gonna make you do anything. If you don’t want to, we’ll go watch a movie instead.”
Sunstreaker’s shoulders slump. He’s silent for a long moment, and then he gestures at the bed. “All right. I’ll try at least.”
“That’s all I’m asking,” Sideswipe says, scooting back. He lies prone, pulling his knees up with his pedes flat. He spreads his legs and indicates for Sunstreaker to kneel between. “I got your gloves.”
Sunstreaker looks at the box Sideswipe holds out. “Is that okay? Should I use gloves the final time?”
“If you want to. I don’t mind. They’re your fingers, so do what makes you comfortable,” Sideswipe replies as Sunstreaker gloves up his left hand. “Oh, here’s some lube too.”
Sunstreaker blinks down at the bottle, then at Sideswipe’s valve. “Do I need it?”
“Heh. Probably not,” Sideswipe says ruefully. He can already feel a trickle of lubricant trail down his valve lips behind his panel. “But pretend I do. Fingers are one thing. A spike is another.”
“The thought of my spike makes you wet, though,” Sunstreaker points out.
Sideswipe shuts his optics and counts to twenty, doing his best not to overload on the spot. “Yes,” he grits out through clenched denta. “Yes, it does, and stop saying things like that.”
Sunstreaker rolls his optics and squirts out a dollop of lube onto his index finger. He rubs it in with his thumb, frowning slightly. “It’s cold. That okay?”
“Yeah, it’ll be fine.” Sideswipe focuses on the little furrow between Sunstreaker’s orbital ridges. It’s better than listening to Sunstreaker utter the words ‘spike’ and ‘wet’ in the same sentence. “So, the sight of a valve itself – is that fine? Any discomfort there? Especially if, you know, leaking?”
Sunstreaker’s gaze flicks up to the apex of Sideswipe’s valve. “No. I’ve seen you wet.”
Sunstreaker was gonna kill him, Sideswipe just knew it. “Good. You’ve felt me up, in and out of the washracks. You wanna start with that before we get to any penetration?”
“ – yeah. I think that should be alright."
Nodding, Sideswipe triggers his panel to retract, grateful he had remembered to fling a towel down to lie upon. He already knew he’d be making a mess; adding the artificial lube might mean a bedding change before the end of the night if there wasn’t something protecting it.
Sunstreaker tilts his head to the side as he stares at Sideswipe’s array. The seconds tick by, and Sideswipe reflexively leverages himself up to also look. “Uh – what? What’s wrong?” Sideswipe wonders if one of his biolights is out. Primus, he hopes not. They’re a pain to have exchanged.
“Nothing. I’ve never really looked before,” Sunstreaker replies. He ghosts a finger down the right side of Sideswipe’s valve, tracing it from top to bottom. Then Sunstreaker slides a finger along the outer lip and gently pulls, exposing Sideswipe’s anterior node. Sunstreaker furrows his orbital ridges again and leans closer.
Sideswipe’s elbows wobble before giving out completely, and he collapses back onto the bed with a quiet grunt. He knows Sunstreaker is just getting a better look, but to see his twin’s helm so close to his valve? He might just overload before they get to penetration.
“Your biolights are blinking faster,” Sunstreaker comments, voice floating up from between Sideswipe’s legs.
“Yeah – yeah, they’ll do that the more excited I get,” Sideswipe says shakily.
“I’m surprised it’s not like a disco in here,” Sunstreaker mutters.
Sideswipe laughs. It always surprises him when Sunstreaker shows off his sense of humor. “Ha. You’re so amusing. Whatcha doing down there?” Sideswipe shivers as Sunstreaker’s finger brushes up against Sideswipe’s anterior node.
“Looking. Hush.”
Sideswipe fixes his optics on the ceiling and clasps his hands together over his abdomen. He tries to pretend it’s a doctor’s hand stroking his folds, but no doctor has ever touched him like this.
“Huh.”
Sideswipe raises his head to peer down the length of his body. “What?”
“You know, it’s not really that bad,” Sunstreaker says. His finger trails down the very center of Sideswipe’s slit, flirting over the entrance. “I mean, yes, there’s an orifice, but it’s not – abrupt. Everything kind of naturally leads there now that I’m looking at it.”
The digit tip slips inward just a bit. Sideswipe’s hips automatically twitch, trying to thrust up into the barely-there penetration. “So – watching the penetration doesn’t bother you anymore?” Sideswipe drops his head back down to the pillow, voice faint. His hands slip off his frame, fingers tightening into the berth covers.
“Well – I mean, it’s weird – but not ‘turn my tanks’ weird,” Sunstreaker says. The finger inches forward, and Sideswipe’s optic shutters slam shut. He does his best not to writhe.
Sideswipe makes a strangled sound, valve throbbing. “That’s – that’s good.”
“You’re going to overload, aren’t you? Your lights are really fast now, and I can feel you tightening down.”
Sideswipe’s hands fly up, and he presses his fists into his optics, vents rasping. “What have I said about talking like that!”
Step Three.
The next night, Sunstreaker is the one who drags Sideswipe into their berthroom, eager to learn about the next step.
“Alrighty,” Sideswipe says, grabbing a box from the closet and plopping it on the bed. “Fingers are one thing. I want you to get some practice with things a little larger." Sideswipe opens the box and starts rummaging through its contents.
Sunstreaker peeks over Sideswipe’s shoulder. “These are your sex toys,” Sunstreaker says. “You never really use them around me.”
“Nope! I’ll take your fingers over a lifeless hunk of plastic any day,” Sideswipe replies, finally grabbing the dildo he wants. It’s of average length and width, nearly matching his and Sunstreaker’s spikes, except bright green.
“You want me to use that on you?” Sunstreaker frowns. “But I won’t be able to feel you.”
Sideswipe turns wide optics to his brother, spark hammering. “Oh – that’s like – the nicest thing you’ve ever said regarding interfacing.”
Sunstreaker gives him a confused look. “What do you mean?”
“Interfacing is often about connection; it’s meeting somewhere on a two-way street. This is the first time you’ve ever indicated you get something out of this,” Sideswipe explains. “That you’re not just indulging me.”
“I like making you feel good,” Sunstreaker retorts. “And it’s not much of a two-way street between us when I barely take a step onto it.”
Sideswipe waves a hand impatiently through the air. “A step is still a step. You can make me feel good just by buying me a present. Or snuggling me. No, you like the feel of my valve around your fingers, don’t you? Not sexually, but you still get enjoyment out of it, right?”
Sunstreaker bites his lower lip. “Yes – it’s – you feel so alive inside – ”
Sideswipe beams. “See? That – I love knowing there’s something about interfacing with me you enjoy totally for yourself. Do you understand?”
Sunstreaker blinks at him before finally nodding slowly. “Okay. I think I see what you’re saying. But – we’re not using fingers today.”
“No, not for today or tomorrow.” Sideswipe brandishes the dildo at Sunstreaker. “You’re gonna use this on me. Then tomorrow, I’m going to strap it on you, and we’ll pretend it’s your spike while you frag me with it. Get you used to the motions – and my motions. Because I might get flail-y.” Sideswipe rubs the back of his head sheepishly.
“More than you usually are?” Sunstreaker looks at Sideswipe in disbelief.
“Waaaaay more.”
Sunstreaker holds the dildo up in mid-air, studying it. “And this won’t hurt you?”
“Definitely not. I still recommend using lube, although you won’t need to prep me. I’ll do that. Want your gloves?”
“ – yes, please.”
While Sunstreaker pulls on his gloves and starts smearing the dildo with lubricant, Sideswipe throws himself onto his back, pops his panel, and begins fragging himself on his fingers. Two slide into his eager valve without any issues, so he uses a third. And then a fourth.
Sunstreaker settles on his knees between Sideswipe’s spread thighs. Grabbing the nearby hand towel, Sideswipe wipes his hands clean and shuffles his feet wider.
“Are you sure this will fit?” Sunstreaker worriedly stares at Sideswipe’s valve. “It’s not too long? Or too wide?”
“If I were a minibot, yeah, probably. But not for our frame size. Go on, it’s okay,” Sideswipe says. He props himself up on his elbow and watches Sunstreaker extend the dildo. The closer it gets, the more Sunstreaker’s hand shakes.
“Sides – ”
“It’s alright. Here, I’ll guide it in, okay?” Sideswipe murmurs. He takes hold of the shaft mid-way down and positions it at his entrance. “Don’t worry, it’s well-lubed and so am I. You just watched me use four fingers on myself, and this is just a little wider.”
“Nn.” Sunstreaker’s optics flick up to Sideswipe’s face, back to his valve, and then back up again.
“Okay. It’s right where it needs to be. Feel the little bit of give there?” Sideswipe pauses, the rounded head pushing past the pleated folds around his hole.
“ – yeah.”
“Good. Now advance it just a little – there you go,” Sideswipe says. His voice is staticky around the edges as the head completely pushes inside, that familiar punch of penetration lighting up his haptic net.
“Oh,” Sunstreaker says softly, seemingly intrigued by Sideswipe’s valve taking the dildo.
“Just like fingers,” Sideswipe says. “Keep pushing. If you want to be careful, just a little at a time. There – oh, Primus, that’s good.”
Sideswipe’s head falls backward, and he stares at the ceiling, optics unfocused. Mmmm – ever since Sunstreaker had started occasionally participating in Sideswipe’s self-servicing, he’d stopped hooking up with other mechs. It had been a while since he’d felt this lovely stretch.
“How deep do I go?”
Sideswipe pulls himself back together and looks at his twin. “You see the flare to the base? Right about there.”
Sunstreaker’s head shoots up. “That far?”
“Yup. There are multiple nodes in a valve. There’s a cluster at the very back of my valve, just above my gestational tank opening,” Sideswipe explains. “This dildo is the perfect length to hit them.”
“Huh,” Sunstreaker comments. He’s studying Sideswipe’s valve intently, almost as if trying to see past the plating to find those nodes. “This far?”
The flared base butts up against Sideswipe’s pleats, and he clenches down on it, calipers restlessly cycling. He ex-vents shakily. “You got it. Ready for the fun part?” Sideswipe grins at Sunstreaker.
“Out, then in, and repeat,” Sunstreaker says, already pulling back. “I’m not an idiot.”
Sideswipe chokes on his reply as the dildo withdraws smoothly and then plunges back in. It moves with a little more confidence than Sideswipe had expected, and it pulls a throaty groan out of him. His elbows wobble. “No. You most certainly – are – not,” Sideswipe says, shivering. He’ll come in no time at all at this point. “Oh, slag – ohh, that’s perfect.”
“Can you overload like this?” Sunstreaker shifts on his knees. “Or should I touch your node as well?”
Sunstreaker’s slicked thumb passes over Sideswipe’s nub, circling it three times before Sideswipe’s overload hits him like an explosion.
His hips buck up, and his hand clamps down on Sunstreaker’s wrist, pulling the dildo into him hard. Sideswipe’s optics roll back in his head, and he cries out so loudly he’s surprised the neighbors don’t start banging on their door. Amid the pleasure swamping him, Sideswipe hears Sunstreaker’s worried voice, but Sideswipe’s body is wracked in shudders, and he can’t reply. It takes nearly a minute before he regains control of his frame, and even then, it’s a tenuous thing.
“ – wipe – Sides!”
“’m’k – ‘m fine,” Sideswipe mumbles, collapsing back onto the bed. His hands lose their grip, and his arms slither down to lie at his sides.
“You scared the diodes out of me!” Sunstreaker rises on his knees to peer into Sideswipe’s faceplates. “What the Pit was that?”
“ – over – load – ” Sideswipe pants. “Big one – told you – get flail-y.”
“What do I do now?” Sunstreaker looks away, and Sideswipe realizes the dildo is still deep inside of him. He reaches down, fumbling at it. Sunstreaker immediately releases it into Sideswipe’s possession and grabs for the towel.
“I overload harder – when my node is touched and – I’m full – ” Sideswipe explains. He raises his other hand and shakily beckons Sunstreaker closer. “ – did good.”
Sunstreaker lies on his side, pressing against Sideswipe. “I thought I had killed you,” Sunstreaker mutters.
“In all the best ways,” Sideswipe says, starting to feel a little more stable. Wow. That had been a good one. He feels bad about scaring his twin, though.
“I’m sorry – probably should have come once on my own before I let you have a go,” Sideswipe says, nuzzling the top of Sunstreaker’s helm. Sideswipe carefully tugs on the toy and shudders as the motion sparks up further, smaller waves of pleasure. He gently begins thrusting the dildo in and out of himself. That last overload had been amazing, but feeling Sunstreaker plastered against Sideswipe's side while his valve is stimulated is also pretty damn good.
“And it didn’t hurt at all?”
“Definitely not. Felt good. Really good,” Sideswipe says reassuringly.
Sunstreaker pushes himself up onto his forearm and stares down at Sideswipe. “I’m sorry I touched your node without asking.”
Sideswipe shrugs as best as he can lying on his back. “Not gonna argue with results, Sunny. It’s fine. But what did you think about the thirty seconds leading up to me going berserk?”
“It – it was fine. Putting something that big inside a valve, even one that isn’t mine, feels – a little wrong, still. I know you enjoy it. I know that. I have every bit of evidence you do, but – “ Sunstreaker trails off with a sigh.
Sideswipe raises his closest hand, the dry one, and strokes his thumb across Sunstreaker’s cheek. Sideswipe's other hand stills. “My brave boy,” He murmurs, his spark full to bursting.
Sunstreaker averts his gaze. “I’m not – “
“Yes, you are,” Sideswipe insists, marveling at his twin. “The things you do for me.” Sideswipe pushes himself up and brushes his lips against Sunstreaker’s. It’s a questioning touch, one which Sunstreaker answers by pressing back firmly.
Sideswipe shudders as their lips minutely slide against one another. Sunstreaker doesn’t like a glossa in his mouth, but he does enjoy these slow, chaste kisses that linger. For Sideswipe, the pressure, the slickness, the knowledge that they're Sunstreaker’s lips is electrifying.
Sunstreaker takes so many steps down the street between them; he just never realizes it.
Easing the dildo out of himself, Sideswipe tosses it further down the bed and sinks onto the pillow. Sunstreaker pulls back, confused. “Don’t you want – ?”
“I just want you,” Sideswipe whispers, nuzzling Sunstreaker’s cheek. “Kiss me some more, hm?”
Step Four.
“I’m nervous.”
“Yeah, I gathered that.”
“I don’t know why. You were fine yesterday. I mean, sort of. You looked like you had a seizure, but you were fine - you’re sure I won’t hurt you?”
Sideswipe shrugs. “I mean, there’s no way to really guarantee – “
“Sideswipe!”
“Listen, we won’t know unless you actually stick it in me, Sunny.”
Sunstreaker abruptly shoves himself backward, and he sits on the heels of his pedes, staring wide-opticked at nothing across the room. Sideswipe hurriedly sits up, hands hovering over his twin’s thighs. Apparently, Sideswipe’s attempt at levity had completely fallen flat. “ – Sunny – “ Sideswipe says cautiously.
“I thought this would be easier than using my hands, but it’s worse. This whole thing was a stupid idea,” Sunstreaker says, voice soft. “You told me it was, and I didn’t want to hear it, but you were right.”
Sideswipe sighs, his shoulders slumping. He’s silent for a moment before speaking. “No, I said it was a bad idea. You know – you never really told me why you were so dead-set on spiking me.”
Sunstreaker shifts his gaze to meet Sideswipe’s optics. His expression is pained. “Because I’m not – I’m your bondmate and – argh!“
His hands ball up into fists at his side, and Sideswipe grasps them, drawing them into the air between them. “Hey,” he says, looking up at his twin. “You’re my brother and my sparkmate, and I love you. Nothing will change that. Would a full-blown interface with you be great? Yeah, absolutely. Do I still feel fulfilled without it? Yes. Absolutely. I have your love and have never doubted that.”
“It’s just – you’re so – !” Sunstreaker withdraws his hands from Sideswipe’s grasp and gestures aimlessly.
Sideswipe watches the path of his twin’s arms, bemused. “I’m so – ?”
Sunstreaker huffs. “I sense it when we merge, you know. You have this constant underlying lust. It’s like you’re always set on ‘simmer’. And I feel like I’m either the cause of it or I’m not helping address it enough.”
Sideswipe gives Sunstreaker a slow blink. “Ooookay. There’s a lot to unpack there. First – did you just compare me to a stovetop?”
“Sides – “
Laughing, Sideswipe leans up and grabs Sunstreaker’s shoulders. He pecks Sunstreaker on the lips before sinking back down onto his heels. “Baby, I’m just playing. If that analogy works for you, it’s fine. Look, I get it. Or I think I do, anyway. We view desire in two entirely different ways. For me, it’s as natural and expected as my fuel pump beating. It’s not my enemy the way it is yours. When your frame builds up charge over time, it’s a betrayal, something out of your control. Especially since you don’t have that attraction to other mechs to encourage you to dispel the charge through interfacing.”
“It’s stupid,” Sunstreaker mutters. He crosses his arms over his chest like a petulant sparkling. The image is a little off, considering he still has a dildo magnetized to his interface panel, but ignoring that, Sideswipe finds his twin utterly adorable.
“It is. For you. But for me, it’s just natural. Yeah, I guess you could say I’m always at a simmer. I’m around you constantly. You’re gorgeous, and I love you. Just because you don’t want to interface with me doesn’t mean I can’t turn off my attraction to you. But I don’t mind,” Sideswipe says, looking up at Sunstreaker as earnestly as possible. “Lust doesn’t hurt me. Every time I say I’m gonna die if I don’t overload, it’s just me being dramatic.”
Sunstreaker considers Sideswipe for a moment before his shoulders relax. “You are the epitome of ‘over the top, ’” Sunstreaker allows.
“And you are not responsible for ‘addressing’ anything. I’m perfectly capable of overloading on my own. I’ve been doing it for centuries. If you want to help, then great. But doing something which makes you uncomfortable is just going to make me unhappy, which in turn leads to no overloads, and defeats the purpose of you trying at all. Remember what I said about interfacing being a two-way street?”
Sideswipe pokes Sunstreaker in the knee. “No steps taken by anyone in that scenario. Or steps taken, but we don’t actually meet up. It’s like we each shuffle off to opposite sides and – okay, I’m getting off track here – “
Sunstreaker shifts his thighs apart with a grumble, making the dildo bounce a little. Sideswipe glances at it, lips twitching.
“I really wanted to do this for you,” Sunstreaker says softly, following Sideswipe’s line of sight.
Sideswipe ponders the sex toy for a second, head tilting. “Well – maybe we still can. Lay on your back?”
Sunstreaker looks confused for a moment before his face clears. “Oh, I see. Like the time you used the dildo on the wall in the washracks.”
“Exactly. Think that would be alright?”
“If you’re in control of things, I’m willing to try.”
They switch positions, and Sunstreaker gets comfortable in Sideswipe’s former spot. The dildo arches outwards from Sunstreaker’s panel in a stiff curve, pointing slightly towards his chest. If the color hadn’t been that garish green, Sideswipe could have easily pretended it was Sunstreaker’s own. Licking his lips, Sideswipe flings his leg over Sunstreaker’s hips. He grasps the dildo and gives it an experimental stroke.
“Sides – wait.”
“Hm?” Sideswipe glances up at his twin. Sunstreaker has a worried line between his optics.
“Gravity would dictate a natural flow of liquids downward,” he says.
Sideswipe stares at him, nonplussed. If they were still on the stovetop analogy, Sideswipe would be rapidly approaching ‘boil’. It isn’t fair for Sunstreaker to expect Sideswipe to understand a string of big words. “ – huh?”
“Are you going to drip all over me?” Sunstreaker’s voice is deadpan. He flicks his gaze down to Sideswipe’s bared valve before looking back at his face.
“Oh. Oh!” Sideswipe sheepishly chuckles. “Yeah, no, you’re right. There probably will be some, uh, spillage. Way more than if you were on top like we had originally planned. Lift your hips?”
Sideswipe pulls out the towel he had placed on the bed in the beginning. He carefully drapes it over Sunstreaker’s pelvis, tucking it around the base of the dildo as tightly as possible. “There. If things get any messier than the towel can handle, I will clean you as thoroughly as if you were doing it yourself,” Sideswipe promises.
“No, you won’t. You’ll try, though, so that’s something,” Sunstreaker says. He gives Sideswipe a small smile.
“Aw, you say the sweetest things, lover. Okay, comfy? Need anything before we start?” Sideswipe straddles Sunstreaker again, hovering over the tip of the false spike. Sideswipe’s valve clenches down in anticipation. His spark is already whirling fast. He’d bet everything he owns he’ll overload in less than a minute.
“No. Do you? Should you like – prepare or something?” Sunstreaker averts his gaze, instinctively cradling the outside of Sideswipe’s thighs as he lowers himself.
“Ha. You’re so funny.”
Sideswipe eases himself down onto the dildo, his valve pleats parting around the head with a moist sound. He pauses a second, more to savor the sensation than because he needs to. Then he sinks the rest of the way until his aft rests atop Sunstreaker’s thighs. Mentally, he decreases his initial estimate to thirty seconds.
“Oh. That was – quick.”
“Hhngh.” Sideswipe’s optics lose focus, and he wets his lower lip. He knows it’s not Sunstreaker’s spike, but it might as well be. It’s Sunstreaker’s waist between Sideswipe’s knees, and familiar gold plating lies beneath his palms. His valve is full, and his processor has been fooled into thinking Sunstreaker is inside him, and if Sideswipe moves even a centimeter –
“ – are you just going to sit there? I’m fine, you know.” Sunstreaker transfers his hands to Sideswipe’s waist and sort of – nudges him. And, well – that’s the beginning of the end. The motion stirs the dildo against all of Sideswipe’s inner nodes, and it feels so good that Sideswipe helplessly swivels his hips to receive that input again. He leans forward to really grind the head of the dildo against his ceiling node, but it accidentally brushes his anterior node against a fold of the towel, and that’s it –
Instant overload.
Moaning, Sideswipe slumps against Sunstreaker’s chest, sensation coursing through him. He floats in it for a little while, blissed out. It’s even better when Sunstreaker’s hand comes to rest atop his head, gently petting.
Eventually, Sideswipe stirs, clumsily pushing himself up on one elbow. Sunstreaker peers at him in amusement.
“That’s it? Are you saying I could have literally just climbed on top of you, stuck the dildo in, and been done? What was I worried about?”
“Shut up,” Sideswipe mutters, rolling his optics. He’d been worked up, way before Sunstreaker’s freakout, although that was a little fast, even for Sideswipe. “And yeah, probably. C’mon, you know what I’m like when it comes to you helping me out. I’ve got the worst hair trigger.”
“Primus. Okay, roll over, I got this.”
Sideswipe yelps and clutches Sunstreaker’s shoulders as he shifts. “No! You lost your chance, mister.”
“You sure? I’m suddenly feeling a lot better about this.”
Sideswipe shakes his head. “I’ll let you try fragging me from the bottom later. But I’m not done.”
He grins rakishly at his brother and circles his hips, feeling wisps of charge gather once more. Sideswipe will let Sunstreaker have a go in a bit, but for the next little while – Sideswipe has plans.
They definitely don’t have a conventional relationship, but Sideswipe doesn’t mind in the slightest. It’s a two-way street, and they don’t always meet in the middle. Some days it’s closer to Sideswipe’s end, and other days it’s closer to Sunstreaker’s.
Regardless, they always meet.
~ End