Mac slammed his hooves against the bed with anger as he sat up, letting his legs drape over the edge of Coco’s (now soaked) bed.

“Uh uh. No. Nope.” He growled. “I’m done.” He continued to try to remove the restraints from his body, his cock now easily 20 inches in length, with considerably thicker girth and full, large, pendulous testicles. “I’ll hoof myself off in the street if I have to. I ain’t goin’ through this anymore.”

Rarity sighed, sitting next to Big Mac, and patting his lap. “Poor stallion, I am ever so sorry. I did intend to let you finish in me just now… but when I saw that Coco had roused, I had hoped…”

“Rarity,” Coco suddenly piped up, in a calm voice. “Y-you should just do what Big Mac wants… this is really not fair to him.”

Mac’s grimace softened slightly, as he looked over at the cute mare sitting on the floor near him. She blushed as she smiled at him, before looking down and pawing at the ground. “H-he’s done so much already…”

Mac felt his heart melt slightly, as absurd as it seemed. After everything he’d been through.

“W-well...” Mac uncrossed his arms, “I ‘spose it would be a darn shame ‘tah go back empty-hoofed.”

Rarity clapped her hooves together with joy and hopped up off the bed. “Oh you are a gentlestallion, Big Mac!” Her horn lit up and within a flash, Coco and Mac’s bridles, saddles and tail wraps undid themselves and whisked away from the pair to land neatly in a bag surreptitiously stashed in the corner of the bedroom.

“H-huh?” Coco asked, looking at her mentor with confusion.

“Oh Coco, you two should take your time with this… no need for accoutrements for such a special occasion.”

“I-I… kind of liked them.” Coco whispered, shyly.

“That’s ‘cuz you didn’t have the ones that stop ya from blowin’ your load.” Mac chuckled, gesturing at the two remaining leather accessories still wrapped around his throbbing genitals.

“Oh hush, Big Mac… you’ll see soon enough why those are so fun.” Rarity chided playfully before turning to Coco, “Well, darling… it seems that you are developing a taste… we’ll have to get you even more accessories for next time…. For now, though… hooves up on the bed, please.” Rarity patted the edge of Coco’s bed, motioning for her protege to clamber halfway up, which she promptly did.

“L-like this?”

“Yes! Perfect!” Rarity clopped her hooves. “This bit should be as vanilla as can be… you two should enjoy some nice, romantic slow tailhole-sex, after all you’ve been through.”

Mac hopped to his hooves, his big erection bobbing up and down under him, smacking against his chest further up his belly than had it had ever reached before.

“Now Mac, your forehooves right here, if you please.” Rarity gestured to the correct spot. “Yes, perfect. Coco, scoot forward… a bit more, yes… just let your hips rest right on the edge of the bed, no weight on your hindlegs at all. Perfect.” With Rarity’s direction, Mac had mounted over top of Coco, his bulk once again dominating over her, though he now tried to avoid touching her in any way, as if she were a delicate flower.

Mac felt her should brush the inside of his left fore-leg, and shifted quickly to avoid touching her, which brought his bouncing cock to slap against the side of Coco’s left Flank.

“S-sorry!” Both Mac and Coco said at the same time, before blushing and looking away.

“Really you two?” Rarity rolled her eyes. “Not half an hour ago, you two were rutting like savages, and now you’re playing the blushing virgins? Coco, turn your head and look up at Mac.”

Coco grimaced slightly, twisting her neck and looking up at the stallion over her.

“Now Mac… tell Coco how you feel about her.”

Mac paused for a moment, trying to assemble his thoughts as he looked down at the blushing mare. “Y-you’re b-beautiful Coco… I’m lucky to be with ya.”

“Thanks, Big Mac… you’re incredible too… and… real handsome…” Coco giggled.

Rarity clopped her hooves. “Very good… now Mac... kiss the filly already.”

Mac leaned in, closing his eyes, as Coco looked up at him and did the same. A tantalizing moment of eternity seemed to pass, before the distance between their two snouts closed, and they connected. It wasn’t a deep or lustful prench kiss, but it was romantic. A gentle kiss where the two lips enjoyed playing and parting with one another.

Mac felt himself wrapping his forelegs around Coco’s shoulders, leaning more weight onto her and pressing more closely against her. Coco, for her part, stroked at one of Mac’s forelegs, softly petting him with caressing strokes.

Rarity carefully chose her moment… using the barest amount of magic, as little as she could manage, she carefully hefted the massive horse-sized cock hanging from Mac’s groin, carefully positioning it so it would shortly press against Coco’s plump little pucker. Simultaneously, she levitated a bottle of specially crafted lube from her bag, an eclectic blend of fragrant oils, moisturizing lubricant, and magical elastifiers… and deftly dribbled a liberal amount on the huge flare approaching Coco’s ponut. She then twisted the bottle, pressing the spout against Coco’s tailhole and massaging a good dollop into her folds.

Mac naturally pressed forward and felt the tight sphincter against his burning cockhead. Coco began to groan more noisily into their unending kiss as her tailhole resisted his huge shaft, stretching inwards as he pressed with more and more intensity, wanting once and for all to bury his dick in a mare’s tight asshole.

“Gentle… gentle Mac… she’ll open… slowly...” Rarity cooed, carefully observing their union.

Mac slowed his advance, letting Coco’s tailhole simply press against his flare, as she writhed and grunted into his lips… Ever so slowly he felt the ring grow, and a BURNING, TIGHT, heat began to engulf his cockhead. Like rolling on a condom three sizes to small, the incredibly small but elastic ‘O’ unfurled and expanded around the point of his cockhead, rolling back and back and back, wider and wider… until… *pop*! Her ponut slipped over the thick ridge of his flare, and suddenly… he was embedded in her.

“Yes… yes.” Rarity cheered softly. “Just rest there now… just feel it, how tight she is… how hot… how smooth. And how full you are Coco… your bottom strained with something so naughty… never meant to be put there.”

Coco giggled into Mac’s kiss, finally breaking it, her eyes fluttering open and looking at Mac’s smiling face demurely, before she turned and faced forward… then began to wriggle on Mac’s cock… feeling the incredible size of his dick buried in her asshole.

Mac tightened his grasp around the writhing little filly and began to slowly press forward again.

Rarity carefully applied more lube to the huge black pole as it slid… impossibly, into Coco’s tight little asshole. Mac’s girth was so wide, that he was pressing into the muscular, pert flanks of Coco’s haunches… and yet still he somehow sank inch after inch into her tiny body.

“Yes, good pace… slow and steady…” Rarity cooed. She watched carefully and saw Coco quiver as Mac pushed his 7th inch of thick stallionflesh into her. “Stop! That’s it for now Big Mac. No more.”

Mac snorted slightly but nodded, carefully squeezing Coco’s hoof with his own to let her know that he wouldn’t go any further. Coco squeezed back, whispering a tiny, “thanks…” as she did so.

“Just enjoy the moment you two…” Rarity sighed, watching with envy.

Mac and Coco were in heaven, just drunk on the sensations. Mac wrapped in a burning vise-like tightness… and Coco filled to the brim with horsecock, her ass completely stuffed. Minutes passed, the two ponies simply breathing and nuzzling with each other, sometimes giggling together, sometimes mewling or moaning. Mac would rub his chin on Coco’s head, only for her to nuzzle his neck… then both would let their lips find each other, as they played and enjoyed the sensation of being stuck together in such a taboo way.

Rarity was about to give her next command, when… at the same time… Mac began to slowly pump in and out… right as Coco start to softly gyrate back and forth. She smiled to herself, happy that she didn’t need to interrupt such a sensual and slow lovemaking session.

She simply watched with happiness as the slow travel of fat stallionhood ground in by two inches, and out by two inches, over the course of ten seconds… again and again… a slow and methodical assfucking that had Coco’s head thrashing about, grinding into the bedsheets as her passion built and built.

Rarity had to admit that Big Mac was a natural backdoor salespony… his cadence and rhythm soon making Coco’s clitoris wink in and out of her dripping marehood. Rarity had worried that she might need to provide the little mare with some additional stimulation to coax her over the edge… but after only a few minutes, Rarity saw the tell-tale spasms roil through her young protege.

“Oh...oh…. B-big Mac!” Coco groaned out, the first words to pierce the silence in what felt like forever. Her rear lifted, spasming with little gyrations as she desperately tried to stuff more of Mac’s cock into her… before she let loose with a large splashing torrent of juice from her pussy that coated Mac’s oversized balls. “F-fuck!” Coco shuddered, before a second spasm wracked through her… sending another squirt of her nectar spraying backward.

‘Now that was unexpected!’ Rarity thought to herself. ‘Multi-orgasmic on her first tailhole penetration? Perhaps my little Coco really is an anal slut.’ Rarity chuckled to herself.

Mac’s hips were starting to buck involuntarily a bit too. The squeezing throbs of the little filly cumming on his cock were coaxing him to his own peak, and Rarity could see that the building wave of shakes rushing through Coco would be the last that Mac could endure. She’d made a promise to the stallion, and he’d done far more than could be expected of any stud this evening… he had earned his climax.

She carefully watched and prepared her magic, gripping the releases of the fasteners on the leather rings barely constraining Mac’s balls and cock.

“Get ready Coco, Mac!” Rarity warned.

Neither could hear her.

Coco had been drooling incoherently into her soaked sheets for minutes now, turning her head left and right as her body shuddered with orgasm after orgasm. Her butt felt so full, so complete! Her ponut had stretched to take everything that it ever possibly could, strained to its utmost… it was everything she ever dreamed… she let out one last lingering groan as her final orgasm washed over her…

Mac’s gritted teeth could do no more to save him. The impossible milking strength of Coco’s tight little ass showed itself in another series of savagely intense convulsions as she came for the final time. Mac felt his own bucks intensify, fully out of his control now, as he drove forward with desperate humps in the agonic-throes of his own climax. Shoving every millimeter of his cock into the burning hot tunnel of Coco’s ass, he felt his flare throb and expand to even more massive proportions, and just as he felt the magical glow threatening to interrupt his ejaculation once again, the much-hated energy fields beginning to kick in…

The two rings released, suddenly pulled away from his body.

…

Mac’s lungs emptied, he was winded. He couldn’t even hear that he was screaming at the top of his lungs.

…

A massive surge tore through his body, racing through the delicate plumbing of his seminal vesicles, vas deferens and ejaculatory ducts. Aided by the magic of the released spell-work… the dam holding back Mac’s flood burst.

He came.

Buckets.

…

Nipping onto Coco’s neck for purchase, Mac felt a bulge course through his shaft like a fire hose, expanding into Coco’s ass… then absolutely erupting from his huge flare. It was less a rope of thick batter than a huge, power-washer intensity stream, that thudded out of him for a full two seconds. Mac’s eyes rolled back in his head at the blissful feeling of pure release at the initial mugful of cum that spilled into Coco’s guts.

But he was just getting started.

Not half a moment after the first stream finished, the second slammed through him.

Then the third… and the fourth… and the fifth…

Coco moaned, her orgasm subsiding just enough for her to regain sensation and awareness of her surroundings… she could feel her belly filling, stretching with the magical cum that Mac was dumping into her with surge after surge, sloshing into her and filling her like an obscene balloon.

And the ninth… and the tenth… and the eleventh…

Coco squeaked in slight fear, her butt now lifting off the edge of the bed from the cum-stuffed bulge in her tummy, the warmth spreading throughout her body as Mac pumped his firehose-like torrent into her. “M-mac!” Coco shouted, fearfully… But Mac couldn’t hear anything… and even if he could… he wouldn’t have been able to stop himself.

The sixteenth… the seventeenth… the eighteenth finally a bit weaker than the others.

Coco grunted, her belly now as large as a pregnant mare, she could feel little squirts of cum escaping from the tight seal between her tailhole and Mac’s throbbing cock, like a water-balloon over-filled to bursting. She groaned in fear… could she… would she… pop?

Finally, with the twenty fifth ejaculation… Mac’s orgasm subsided...

He tottered slightly, falling backwards without any strength left in his body, caught gently in Rarity’s blue magical aura and gently allowed to fall to the ground. As he fell away, his exhausted and rapidly shrinking cock… which had been stock hard for the better part of two hours now, quickly retracted and diminished, slipping out of Coco’s strained tailhole with a nasty splorch, leaving a small fountain of his cum trickling from her rear like a popped champagne bottle… before her asshole finally closed and retained his deposit.

He lay on his back, shuddering and twitching, looking up at the ceiling with a goofy smile, all sounds and sensations only coming to him distantly… as though through a filter that was muffling everything.

“Careful dear… I fear you’re fit to burst, that’s it… one hoof after another.” Rarity’s voice dimly rang in his ears.

“Oh Celestia, Rarity! Look at me! I look like I’m pregnant with triplets! How am I going to open shop tomorrow!?” Coco’s groan came from the other side of the love-drunk farm-stallion.

“It’s Friday darling, you have the whole weekend… I find the spell usually clears up in a half-day or so…”

Mac heard two sets of hoofs trotting over toward him.

“Just look at him… typical stallion!” Rarity chided jokingly, “leaving us poor mares to clean up the mess as he basks in his conquest.” She prodded him in his side, using a bit of magic to lift his head up so he could see the two mares standing over him, one a complete sweaty mess, the other with a belly so stuffed with cum that that it nearly touched the floor. “Well? Look at what you’ve done you rogue,” Rarity chuckled playfully, “just what do you have to say for yourself?”

Forcing his eyes to uncross and refocus, Mac stumbled with his heavy, unresponsive tongue, remembering the one thing that he had been told by his future fiancé should the evening prove successful.

“H-h... how… how do yew two feel about herds?”

Author's Note

Awww!

I hope you all enjoyed this (not so) little fic.

I started out writing this as something to publish just before I do my interview with the lovely community podcast: The Barcast!

I hope you come hang out at 7PM EST tomorrow in the Discord for some good times and a few laughs.

That being said... this fic quickly got a life of its own... going from being originally a small 5000 word fic... to the monstrosity it is now!

As I kept writing, I found Rarity's domming to be incredibly hot, and just had to keep expanding the scenario... am I a closet BDSM fetishizer? Maybe!

Anyway, I hope you liked this little journey as well, where I continued to use giant stallionhoods to absolutely destroy mares... it's such fun!