(Takes place before the series finale)
Spike stared out the window of his cabin, as the train went down the mountain from Canterlot to Ponyville. It'd been a couple weeks since he last visited his old home, as he'd been helping Twilight handle the diplomatic conference between the changelings and kirins. A race of super-empaths meeting with a race with fiery, angry outbursts? Definitely not a trip he'd recommend, even if it was nice to hang out with Thorax and Autumn Blaze. All he wanted to do now was go home, sit in his comfy chair, and relax in the arms of his lady.
Becoming a teenage dragon was hard for... well, everypony, but especially himself. His hormones were constantly in overdrive, his emotions at eleven, and he felt himself fall for SO, MANY, GIRLS! Rarity of course was his Number One, the mare who was always in his life (save for Twilight). His affection for her had gone unreciprocated for years, but once he started growing (and looked more like a beefy dragon boy instead of a cute child), the fashionista started taking a much greater interest in him. She kept asking for him to "help her out" with various projects, but now these daily outings were rewarded with lunch and dinner dates, little outings at the park, and on certain occasions, hugs and kisses that weren't strictly-speaking platonic.
But as much as he'd want to capitalize on going out with the "10/10" Element of Generosity, by that time he'd already picked up a few additional love interests.
First, there was Smolder. Sister to Garble, the dragon who bullied him when he first went to the Dragonlands, the feisty orange dragoness had been teaching him all about dragon culture ever since she arrived at the Friendship Academy. Her interest in him, while initially sisterly, quickly changed once he grew wings. Their training sessions soon started taking on a more flirtatious, romantic vibe, as she started making her intentions more obvious. Being a female of his species, it was hard for him to resist the offer, as his maturing body began to respond to all the pheromones in the air.
Then, there was Gabby. The sole griffon of the Cutie Mark Crusaders, they met on her second trip to Ponyville. She was fun, and funny, and had so many stories of the world beyond Equestria. After one day of hanging out, it was like they'd known each other for years. When she invited him to her guest room for a prolonged makeout session, he jumped at the opportunity. It was amazing, the way her tongue danced in his mouth, the way her talons went up and down his spine, the way her feathers and fur rubbed against his scales felt like heaven. But Twilight had raised him to be a gentleman, and he didn't want to go and lose his virginity to someone before they had their third date. So he gave her a (long, passionate) goodnight kiss, bid the griffoness adieu, and went home with the promise to do it again sometime.
By the time Twilight had asked him to come along for the trip to the Changeling Hive, he was torn between three loves. Did he want to pursue his old crush? His new best friend? Or the hot, intense fling?
As the train pulled into the station, Spike remembered the fateful day when all three of them came to him, and revealed that they knew of his relationships with all of them. Boy, was he terrified! It felt his heart was going to explode out of his chest and his blood turned to ice! Surely, there was no way he could get out of there without two of breaking the hearts of two of his favorite people. And yet, something unbelievable happened: Smolder explained to them that dragons are naturally polyamorous, and often have multiple mates at the same time. In fact, Ember's father was known to have as many as thirty partners at one point, and one male with three females was pretty common in the Dragonlands. The three ladies had spoken together about what to do, and - considering that Spike was such a great friend and most eligible dragon bachelor in Equestria - they agreed that they wouldn't mind sharing him with each other.
Even now, Spike couldn't believe it. He thought he lost his chance with three of the most beautiful creatures in the world, but instead had been awarded three girlfriends! Sure, things could get complicated balancing all his responsibilities and managing the drama between the three feisty ladies, but this was more than made up for when all four of them could come together. Picnics in the park, nights out in the most exclusive restaurants in Canterlot and the Crystal Empire, even winter evenings spent cuddling together by the fire were wonderful moments Spike would take with him for the rest of his life.
Alas, life often had a way of interrupting good things. Gabby had to hit the road again, travelling the world to help others find their cutie marks or purpose in life. Smolder had to return to the Dragonlands to help take care of his brother's new eggs. For the past month or so, it was just him and Rarity, and with her career working fashion and his working politics, they could go more than a week without seeing each other. It's why this return to Ponyville was so awesome - the Winter Fashion Season was over, and with the Spring Semester starting up, both Rarity and Smolder would be in Ponyville at the same time. Spike hadn't heard from Gabby in awhile, but he'd take having his pony and dragon girlfriends together over having none of them.
His reverie was cut short, as the train came to a stop at the station. Spike got up, gathering his suitcase and backpack, and made his way off the train. He stepped onto the platform enveloped in a cloud of steam and smoke, as dozens of other pony passengers. Technically he could've gotten off at the front with Twilight, but he had someone waiting for him. Besides, he saw how his sister/mom had been staring at the backside of that golden, blue-haired pegasus guard. He'd let her get some one-on-one time with him, in exchange for getting some personal time with-
"Oh, Spikey-wikey!" A familiar, beautiful voice called out, making the dragon's heart flutter. Looking through the crowds, he spotted her, ivory coat shining like a beacon, blue mane and tail waving in the breeze.
"Rarity!" He shouted, wading his way through the mass of ponykind. In a few short steps, he reached her, lifting her up in his strong arms, pulling her into an embrace. The unicorn rewarded him with a kiss, her heavenly perfume filling his nostrils and fueling his passion. "Oh Celestia, I missed you!"
"I missed you too, my big handsome dragon!" She giggled, as they rubbed noses together. "How was your trip, darling?"
"Very good," Spike said, putting her down as they took their bags off the platform, "Thorax says hi, by the way."
They made their way from the train station to Rarity's home and boutique, chatting about things that happened at the Hive and in Ponyville during their separation. It felt good to talk to her again, to feel her flank rub against his leg, to see the twinkle in her eyes. It was like old times, when he used to hang out with her as a young dragon. Only now there was a little something extra between them. There was that hint of sexual tension in the air, a desire in both parties to experience each other in the most intimate ways. The dragon and unicorn had gotten frisky with each other these past couple of months, engaging in a fair amount of groping and rubbing and teasing. But Spike still remained a virgin, respectfully holding back both for Rarity's safety, and as he tried to figure out his relationship with all three females.
As they approached her home, Rarity sighed. "Oh, I'm sorry, Spike," She said, "I just realized I forgot to pick up the cupcakes for tonight. Would you mind terribly popping over to Sugarcube Corner and getting them?"
"Oh...Yeah, no problem." The request caught the dragon off-guard, but it didn't bother him that much. Besides, he wouldn't mind visiting Pinkie Pie and the Cakes. He handed his bags to the unicorn (who levitated them all inside), and he made the quick walk over to the bakery. It was after the lunch rush, so the wait in line was mercifully short.
"Hey, Spike!" Mrs. Cake greeted him, as he approached the counter. "Good to see you again! I take it you're here for Rarity's order?"
"Yes, ma'am." The dragon answered, spotting a box big enough for a dozen pastries, marked with a diamond-shaped sticker. "Is this hers?"
"It is," The MILF-y mare replied, "Pinkie made them. They're specially made with a couple secret ingredients. I'm sure you two are going to have a lovely time tonight." The Earth Pony gave him a knowing wink, as she hooved over the box. He took the box, pondering what she meant as he returned to the Boutique. Did she know if Rarity was planning something for him? He doubted the unicorn would tell anyone, but Pinkie being Pinkie, the Cakes probably knew before Rarity did.
When he went inside the Boutique, the lights were off. "Rarity?" He called, looking around the main floor. "Rarity? I got those cupcakes. Where are you?"
"Up here, darling!" She called seductively from upstairs. "Can you help me with something, please?" Spike thought he heard giggling. Multiple giggles.
Oh, no way! A smile crept over the dragon's face, as he ascended the stairs. He went to Rarity's bedroom, opened the door, and what he saw stopped him dead in his tracks.
"Smolder?" He gasped, "Gabby?"
"Surprised?" Rarity teased, setting off another round of giggling. Laying in Rarity's bed, adorned in frilly lavender lingerie, his white unicorn laid between an orange dragoness and a gray griffoness. They all looked at him with playful, seductive eyes, their outfits accentuating their thick, round buttocks. Lines of silk drew his eyes to their crotches, emphasizing the tiny pink nipples poking out of their fur.
"Wha-What're you..." Spike stammered, lowering the box of cupcakes over his crotch, "I don't understand."
"Spike, do you know what today is?" Rarity asked, eyebrow raised.
"...The day Rainbow Dash did her Sonic Rainboom," He suggested, "And you all got your cutie marks?"
"Yes, darling, but what else?"
Spike paused, trying to think of what it could be.
"It's your hatching day, dude!" Smolder declared, slapping her head in a "duh!" gesture. "How could you forget?!"
"...Oh yeah." Spike blinked, now that it all clicked in his head. It seemed dumb that he would forget, but when your big sister/adoptive mother discovered that her destiny became interlinked with her best friends the same day you hatched, you learned to take the back seat to all the festivities and planning.
"So Rarity reached out to us," Gabby added, "Saying that she knew everything between us, and that she wanted us all to give you an extra-special present."
"It was definitely a surprise for us," Smolder said, "But we were down with it. After all, who wouldn't want to have a foursome with the two biggest heroes in all of Equestria? There is, however, one condition, before we continue."
"What's that?" Spike asked.
"I need you to finish in me!" Smolder declared, sitting up in bed. "My heat's kicking in again, and I need to be bred by a dragon stud, dude! Don't worry, Twilight's been giving me some dragon egg control, so you don't have to worry about being a dad right now. Though if you want, we can pretend that you're trying to breed me." She gave him a playful wink, though the way she bit her lip made him think that maybe she wouldn't mind having an egg or two.
"So whatcha think, Spike?" Gabby asked, teasing him with a flirty wiggle of her rump, dewy drops of lust lining her pussy. "Are you gonna keep staring, or are you going to ravage us like the big, bad dragon we know you are?"
The dragon didn't need any extra encouragement. He put the box of cupcakes away, revealing his growing erection. Seven inches of dragon cock emerged from his slit, red and thick at the base with fleshy barbs around the tip. All eyes locked onto the shaft as he approached, thick meat throbbing in anticipation. All three females sat up and scooted to the edge of the bed, staring hungrily.
"So that's what it looks like." Gabby mused, lightly stroking the member with her talons. She pressed against the barbs, smiling as it easily bent and moved. "Lot more give than the barbs on a griffon cock."
"You got that right." Smolder agreed, leaning in to breathe in his musk. "There's nothing better than the scent of dragon dick."
"I have to agree, darlings." Rarity added, her horn glowing as Spike felt a pressure surrounding and massaging his member. "The moment Spikey-Wikey hit puberty, his smell became absolutely irresistible. I couldn't stop thinking about what his stallionhood looked like, what it would feel like inside me. What it would taste like."
Without any further prompting, the unicorn leaned forward and licked his dickhead. Taking this as an invitation, Smolder and Gabby joined in, lavishing his penis with licks and kisses. Spike closed his eyes, let his head roll back. This had to be a dream, it was far too good to be true. At any moment, Luna was going to show up and tell him he'd been punk'd or whatever. But no, the sensations were all too real. The claws grabbing his ass and pulling him close was too real. The panting and slurping the girls made was too real. The feel of three tongues on his cock was all, too, real.
"Oh Celestia," He whispered, "This is too good."
"We're just getting started, darling." Rarity giggled, and the three girls repositioned themselves. Rarity climbed on top of Smolder, their bellies and pussies rubbing together. Gabby climbed on top, hugging the unicorn as her crotch rubbed against her rump. As far as Spike was concerned, going pantyless was a great choice. They all looked back at him expectantly, hungrily.
Spike licked his lips, his cock throbbing with aching need. One hand took his member, guiding it to the glistening slits, while his free hand cupped Gabby's thicc booty, spreading it. He buried his face between those cheeks, breathing in that feminine musk, kissing her soft lower lips. Gabby cooed, delightful chills running up and down her spine. He licked the sweet nectar along her griffon pussy, and slid himself between Rarity and Smolder's crotches. All three women moaned in pleasure and delight.
"Fuck, Rarity," Smolder gasped, "This feels ama-" But she was cut off, as the older unicorn leaned in and kissed her, deeply and passionately. The dragoness melted under Rarity's kiss, pulling her close as their tongues wrestled and danced in her mouth. She didn't taste like marshmallow like everyone in school believed, but Smolder found her just as tasty.
Spike see-sawed between his three lovers, moving his tongue and his dick back and forth, back and forth. The bedroom was filled with the sounds of moaning women and the schlick-schlick-schlick of wet flesh on flesh. His belly was tickled by the wagging of Rarity's tail, while his own was being coiled up by Smolder's, and Gabby's hung over his shoulder, flicking between his wings.
"Mmm, c'mon Spike," The griffon challenged, "Pick up the pace! There's three of us you have to take care of now!"
Spike smiled. If they wanted him to go faster, he'd give them faster alright. He increased the speed of his thrusts, even as his tongue wiggled and danced inside Gabby. All three girls yelped and moaned with pleasure, becoming overwhelmed by the barrage of the dragon. His dick slipped into Smolder, and to compensate, he slipped his fingers up and into Rarity's pussy. Fingering, fucking and eating his favorite women in the world, the room filling with the sounds and scents of sex, he couldn't help but think he couldn't help but think that was the best moment of his life.
"Fffuuck, that's it!" Gabby cried, squeezing Rarity and Smolder in a bear hug. "I'm getting close! I'm getting close, Spike!" Based on the sounds the dragoness and mare were making, they weren't far off either. Fortunately for them all, Spike had learned that male dragons could cum on demand, and the thing he wanted most of all was for all four of them to cum at once.
Oh Celestia! He thought to himself, as he willed himself to get close. This is it! I'm gonna... I'm gonna-
He moaned loudly as his balls clenched, hilted inside Smolder, and came. Hot, sticky nut shot out of his dick, filling the dragoness's fertile womb. At the same time, the hand fingering Rarity found her clit between his thumb and index finger, and gave it a little squeeze. Finally, he took Gabby's clit in his mouth, giving it a little suckle. All three came together, screaming their ecstasy to the heavens. Pony, dragon and griffon juices coated Spike's hand, crotch and face.
They held this position for what felt like an eternity, but was only the better part of a minute. Their screams and moans deflated into pants and grunts, and Gabby and Spike fell onto the bed. Rarity climbed over to rest at Spike's side, as he took her and Gabby in each arm, Smolder cuddling up to the griffon's back. All four creatures laid together, panting and enjoying the afterglow of their lovemaking.
"So," Rarity asked after a time, kissing the dragon's neck, "How was your first time, darling?"
"...Perfect." He replied, a dumb, happy smile on his face.
"Same." Smolder chipped in, reaching over to rub Spike's chest. "My cooch's still tingly. I think this'll handle my heat for a while. Thanks, dude."
"I always knew you had a magic tongue," Gabby giggled, "But damn, I haven't cum that hard in, well, forever!"
"Do you girls wanna go again?" He asked, sounding eager and cock already starting to harden.
"I know I do!" The griffoness chirped, climbing onto his lap, rubbing her moist pussy against his meat. "I wanna know what dragon dick feels like inside me!"
"Don't worry, Spikey-wikey," Rarity whispered into his ear, "You have us for the rest of the night. And we're not going to stop until you've filled us up with your spunk. Now be a good boy and give mommy a show..."
And so he did. On and on and on, all through the night, until each of their holes had been filled, and the dragon was truly and utterly spent. Only then did sleep finally take them, with the promise of a new day fresh approaching...