Zipping out of one train care is a cinch for Rainbow Dash, and she takes the opportunity to stretch her wings a little. She can still feel a little bit of Applejack’s cider in her system, and what better way to burn off the extra calories than by getting a little practice in?

Well, she can think of one way. She zips into the night sky, grin slowly getting larger and larger as she imagines the stallion of the herd having his way with her. Or her with him. Her fantasies keep plowing into each other like her heat-stricken body wants him to plow into her, resulting in a mish-mash of scenes so erotic that were it physically possible to move between them in sequence, she’d get pregnant just by thinking about it.

However, since the variations her fatigue-and-cider stricken mind cook up aren’t, technically, possible for three - much less one - stallion to pull off, she remains assuredly not pregnant.

Yet.

Something her body desperately hopes changes, and her mind keeps going back and forth like the horizon as she completes a few barrel rolls.

Spitfire was going to make an exception for her.

Rainbow Dash grits her teeth as she blasts a huge stylized ‘S’ out of one of the low hanging empty clouds: first, half a wingtip roll to flip herself over, then half a barrel roll to right herself going the opposite direction - the order is important, as it’s easier for her to keep her head on the inside of the loop than the outside, not only because she can see where she’s going better but because of egghead physics that she understood innately but Twilight loved to explain - then repeating the maneuver.

She admires her hoofwork, the wispy white contrails quickly fading into nothing. Could use a little tightening on the turns, though. Maybe she shouldn’t do a complete one eighty on the barrel roll? Instead, less of a turn, giving the ‘S’ a bit of a slant in the middle?

There’s something she’d like in her middle.

Ugh. Rainbow keeps one eye on the train below as she tests the variation, though she still isn’t happy with the results. She can’t think straight this late at night. That awesome mental image, her vision of the trick, keeps getting clouded by bits and pieces of certain other images, fragments fouling her performance like a clingy pink cloud.

Rainbow turns, diving towards the ground; landing on the speeding train as easy as a shift in perspective, which she executes flawlessly. Except the door is stuck, or latched, or something. She knocks twice, her hoof banging against the metal.

A raspberry aura slides the door open, a bright white eyed Twilight peeking out from stacks of wooden logs. “They ready for me?”

“Nah,” Rainbow Dash says as she zips inside, landing next to a comatose Doug and Starlight Glimmer. The human has one arm loosely held around the unicorn’s body, her head resting on his chest. The car reeks of musk and sweat; she’d say they should air the place out if it wasn’t turning her on so badly. "You should be fine, staying here the rest of the night."

Rainbow's eyes drop down to Doug’s limp member, glistening in the light of Twilight’s horn as she shuts the door. Looks like he didn’t even bother wiping himself off after he finished in whichever mare; she can smell both of their excitement in the air, and he’s laying like he just finished laying with Starlight. Well, she should fix that.

Rainbow remarks, “You know, you look like Celestia, staring at Starlight’s belly like that,” as she flits past the two sleepers, landing on Doug’s legs on the other side. Oops. He shifts, but that just gives her better access. Her tongue laps out, starting at the base of his drenched shaft and working her way towards the tip. Definitely not Twilight, although she hasn’t tasted alicorn Twilight yet. But it doesn’t smell like her. So, unless Doug has a third mystery mare stashed on the train, it’s Starlight’s juices coating him.

“I just wanted to see it when it happened,” Twilight says defensively; it’s hard to tell with the pupil-less white of her eyes, but Rainbow Dash thinks they flicked in her direction. Whether envious of what the pegasus is doing to their stallion, or maybe wishing she got a little more of the action?

Rainbow Dash can feel Doug hardening quickly, though she can’t quite place if he’s gone once tonight or twice. Seems more like once, from how quickly he’s growing and twitching, just begging for her to take him in all the way. Well, he’ll just have to wait until she’s good and ready. She stretches in a little further, nose barely needing to prop his definitely not flaccid member up as she licks his balls clean, then his inner thighs. Jeez, Starlight must need to get laid more or something, it can't be good for a mare to be that pent up!

“Sometimes,” Rainbow Dash remarks as she pulls back a little, letting Doug’s head flop to the floor so she can attack the top side, “it takes an hour or two. Celestia was always really vigilant, practically kept one eye trained on it the whole time.” Her tongue draws a long line from tip to base, and she relishes how it jerks again, trying to push its way into her. Don’t worry, big guy. Dam’ll be there soon.

“That would make sense, and given that I just cast the spell I might need to wait a little longer. Good thing I’m not that tired.” Twilight can’t help but watch as her herdmate gets the fur of her neck coated in her own saliva. Her mouth twitches as she tries to suppress her smile; the picture in front of her is almost too good not to save to memory.

“You better not say it,” Rainbow Dash says, glaring at the alicorn. The cock hugs her neck, spasming back and forth to slap at her cheek.

“What?” Twilight replies innocently. “I was just going to say how adorable you look.” She licks her lips. “It’s a good look, too.” She slides forward, light clop of hooves against the floor as her mouth opens up, like she’s going to be the one taking Doug inside her.

No way that’s happening! Rainbow Dash beats her to the buck, pulling back slightly and tilting her head forward. Doug’s rock hard cock needs no support to stand on its own, practically launching itself upwards and into her waiting maw.

Rainbow Dash’s wet lips close around his head, relishing the mix of cum from his earlier tryst with Starlight and the precum forcing it out. Sweet, with that little bit of gooeyness so different than any fruit drink.

She swallows the delicious concoction, which only leaves her desperately wanting more. She effortlessly takes him in the rest of the way, tongue lapping at the base of his balls and drawing an excited moan from the human. She traps his cock against the roof of her mouth before pressing her tongue solidly at the base, depressing that little tunnel that has pumped his seed into her again and again.

She slowly, deliberately slowly, so slow her body screams at her and she can see the muscles in his arm jerk - like he has to hold himself back from gripping his hands around her ears and slamming her up and down on his cock until that tantalizing torrent sprays into her again - draws her tongue up his shaft. Everything that hadn’t oozed out of him before dumps itself into her, starting at the back of her tongue and working its way forward as she reaches his twitching tip.

Rainbow Dash grins, Doug’s cock in her mouth as she meets his eyes. She can practically hear Twilight taking snapshots, though she wouldn’t care if they got posted all over Equestria. She’d put them up in her room, maybe even on top of her Wonderbolt posters!

Okay, nothing trumps her Wonderbolt posters. They could go next to her Wonderbolt posters.

Rainbow Dash swishes the second load around a little, spreading that rich taste to every corner of her mouth. She can feel that desire in him stirring again, but her stallion never gets impatient with her. Especially because she never leaves him hanging!

Rainbow Dash swallows, tongue drawing an excited moan a final time before the real fun begins. She bobs up and down on his hard cock, faster and faster until she’s just a chromatic blur at his crotch. His hands, those devilish monsters, come up to her ears. Not forcing, or guiding, or even trying to help. Just set in that perfect spot just above her head, rewarding her with an ear scratch every time she pulls up to his tip.

She makes sure to hit that spot every time before slamming back down, taking his entire length in. His low moans only spur her on, and it’s nearly enough for her to blank out that niggling sensation that his precious seed is about to go in the wrong hole. She ignores it, years of practice at pushing through pain and discomfort letting her focus entirely on the throbbing member deep in her muzzle.

His breathing gets quicker, huskier, that odd sensation where she can’t tell if he’s trying to hold out longer, stretch out how much pleasure she’s giving him and he’s giving her - as if she would ever deny him a second or third or fifth go - or if he’s pushing himself as hard as she does, and relishing every second of it, only wanting to get to the best part as fast as they can.

Oh, and she’s relishing this, especially as the muscles in his legs tense, and she knows what comes next. Oh, how she knows, and can’t help but smile at once again giving her stallion that greatest of pleasures. She pulls back, giving herself as much room in her mouth as possible, her tongue flicking back and forth on the opening. She blocks the first blast, diverting the copious amount downwards, then the second. She frowns, only slightly, as he seems to give out after the third. Well, it is his second time that night, and it’s still way better than any other stallion she’s heard of. Not that she would ever think about leaving.

Rainbow Dash pulls off with a small pop, grinning madly as a strand of cum stretches from his dick to her mouth. “Enjoy that, big guy?” she asks almost redundantly, winding the trail inside her mouth with her tongue. His broad smile, hands scratching appreciably at her ears, every now and again giving a slight tug to invite her to slide closer to him. She eagerly complies, dragging her barrel along his slick cock until he rests between her teats.

A flash of annoyance crosses Rainbow’s face, as Starlight - still conked out - is occupying her favorite spot. Well, there’s still room on the other side, and a hoof rests next to his head as she draws in for a long, wet kiss. His hand cups her head, fingers digging into her mane, forcing them together. She’d use her tongue, but she doesn’t want to give up any of that seed still dancing in her mouth.

“You know,” Doug says as they reluctantly break away, “Celestia was telling me about some ancient mating practices ponies had, way back in the day.”

“Oh?” Rainbow asks, snuggling next to that furnace of a body. She can feel him getting hard again, pressing into her, almost demanding her innermost sanctum be opened to him once again. “I bet she knows all kind of kinky things.”

That hand comes up to her ears, eliciting an elated moan from the pegasus. Except, Rainbow nearly frowns at the delay in his response, it getting worse as he stops and just holds her. Well, it’s not surprising; Doug never liked reminders of their previous flings, not that Rainbow had any. It was more a thing for Pinkie Pie, or Trixie, or she assumes Starlight. She doesn’t care for it either, Loyalty and all that, but you can’t change the past.

“Hey,” Rainbow says, almost reluctantly. She nuzzles him again, then spots a tiny bead of white on his lips. How’d that get there? A quick lick cleans him right off, then another soft kiss. “You’ll be the first to fill her belly with a foal, Celestia willing.”

Hmm, that sounded better in her head. Well, maybe it works. Screw it, she’s going with it.

Doug chuckles as his hands revive their stroking, pressing her down and into that chiseled chest of his. Then they start pushing, a long, meandering path down her sides under they reach her flanks, stopping right on her cutie mark.

And then he grips her flanks; her tight, taut muscles and little else offers barely any give. He always does this, lets her choose how far she wants to go. And every season she turns him down, and it is always the hardest thing in the world for her to do. Harder than performing a Sonic Rainboom, harder than hearing that Scootaloo would never fly. That betrayal, even if it wasn’t, that yet again she’d be denying him her purpose.

“It isn’t an act,” he says reassuringly, grinding his shaft against her teats. Her breathing gets husky; she loves it, more than any of the other mares in the herd, when he mimics a foal and plays with her. “Or a position, or some fetish.”

Rainbow Dash raises an eyebrow; what kind of things had they been talking about, then?

He leans in close, whispering in her ear; she can see Twilight’s ears twitching, too - alicorn must have impressive hearing.

“It’s a promise.”

Rainbow Dash smirks. “Come on, you big lug,” she retorts, playfully flicking her mane into his face. “There’s nothing I wouldn’t promise you.”

“I was afraid you’d say that.” Doug’s hand moves to her belly, so dangerously close to sending her past the point of no return. But then he stops, just resting his hand where Scootaloo lived for eleven months. Tantalizing her, sending electrics shocks just by lightly dragging his fingernails back and forth, swirling the thin hair.

“Because it’s more than just a promise from you to me.” Doug’s other hand leaves her flank, brushing past her wing to caress her cheek. His thumb plays with the corner of her mouth, eliciting a grin as she pops it inside and suckles. His light moan is music to her ears, the hand on her belly duplicating the motion on her tummy. Oh, and how she wishes it was just a bit further back, rubbing and pumping into her…

“It’s also a promise from me to you.” His hand presses into her belly, then holds its place; his thumb finds her tongue, lightly depressing the appendage still wet from his seed. “To always be there, to care for you in every way possible. More binding than a simple agreement to herd together.”

Rainbow Dash pauses, no longer pulling his thumb deeper into her mouth and miming the fellatio he loves. Herding isn’t something most mares take lightly, even if they ‘herd up’ pretty rapidly. After all, if the stallion is good enough for one friend, he’s good enough for all of them, right? And it’s pretty rare for a herd to break up without something devastating happening.

“And the Princesses would have done this with you?” Rainbow Dash demands, her words slurred from the thumb in her mouth. She returns, aggressively sucking, lightly nibbling on his knuckle. She can feel her body shifting, pushing further up his body, getting herself ready for him.

“Luna didn’t say no, though I didn’t exactly ask her outright.” Doug’s hand leaves her belly, just to find its place squeezing her flanks again, then traveling to her tail. She hasn’t paid much attention to the chromatic hair; it’s probably been thrashing about uncontrollably. But now he wraps his hand, again and again until the strangely strong strands bind him to her, leaving him in complete control of her dock.

Rainbow Dash finds herself pushing forward again, a hoof reaching out to pull him to her again, their lips meeting despite his hand still in her mouth. “Anything Luna does, or Celestia for that matter,” Rainbow vows, “I can do.” She smirks as she kisses him again. “Better.”

“You don’t know how much I want that,” Doug says huskily, then immediately recants at her imposing glare. “Or, you do. The promise is for me to always provide for you, anything you need. And for you to give of yourself, freely and without reserve.” He kisses her again, and presses his thumb to her tongue, and the other dips lower to her marehood. He traces the edges of her outer lips, leaving her gasping in pleasure.

“And it is sealed by me filling you, belly and womb, with my seed.”

“Done.”

There is absolutely no hesitation in Rainbow Dash’s voice, immediately scooching forward. Her mouth envelops his, his hand lost in the rapid motion, passion filled kisses that leave her gasping for more.

Especially as her heat makes itself known again. Her body had been content before, graciously playing along as if it knew she would just clamp down on it and ignore the pain should it try to assert its dominance. But, now that she is in the throes of pleasure? That burning desire, that desperate need to fulfill her duty as a mare, returns in full force. She can't even call it a betrayal by her own body, merely utilizing carrot and stick in the perfect balance to get her to do what she should have done long ago. And, Celestia willing, would do with him again and again, until the world is swarmed with their offspring.

Doug takes no prompting at all, his hand swiftly maneuvering himself just in time for Rainbow to slam her hips down. Perhaps she was just trying to tantalize him a little more by rubbing him against her snuggly foal factory, or maybe she knew her stallion like the back of her hoof. But he’s perfectly positioned, her slick marehood greedily accepting his full length on the first thrust.

Her walls, slick with arousal, massage and caress him, and she eagerly takes the lead. How Starlight manages to sleep through Rainbow rocking her stallion, she’ll never know. But rock she does, pounding herself over and over until her legs burn like the inferno raging inside her.

And when it feels like her legs are ready to give out Doug takes over, one hand slipping behind her mane and locking her lips to his. The other goes to her flank, squeezing at intervals such that she can’t predict when the next one will come. This only gets her heat burning hotter, her walls coaxing him to give up his seed to her innermost depths. To make her his, and him hers. Forever.

His breath, already a little worn from bucking a foal into Starlight, gets even more ragged. He tries to pull himself away, taking hard gasps, but Rainbow doesn’t let him escape so easily. Her hooves wrap against him, holding him against her, breathing through her nose while he steals her breath away.

She can feel how close he is; maybe it wasn’t quite ten seconds. Her marehood clenches, years of experience drawing him swiftly to their explosive conclusion. Rainbow Dash grins as she forces him as deep as she can, that shuddering whipping through his body like her through an obstacle course.

And there had been far too many obstacles on this road of theirs. She moans loudly, passionately, then she screams in ecstasy as her body blankets her in pleasure, just as he blankets her insides with his seed.

Rainbow Dash collapses on her stallion, head laying next to Starlight’s, body writhing as his hands again grip her sides. He takes a deep inhale of her musk, both of them having worked up quite a sweat. She returns the favor, nostrils filling with that pungent odor.

“I feel like I should qualify,” Twilight says; how the egghead managed to watch them the entire time and remain silent? Maybe she’ll have to thank her later for not interrupting. “That filling the womb is more than the simple act of sex. You do need to get pregnant.” She leans in close, whispering in Rainbow’s ear, just loud enough for Doug to hear. “So, let me be the first to say. Congratulations on your new colt, Rainbow.”

Tears well up in Rainbow’s eyes, but her hooves are too busy locking themselves around Doug to wipe them away. Her mouth quivers, worse than when she had to say goodbye to Tank. Her body shudders, not yet ready to give up its prize or the seed safely trapped inside her, even if they had already done their job. Magnificently.