Vinyl thinks that Octavia is one of the biggest prudes in all Equestria. Then Octavia ascends one day after writing and playing a new piece of music solo. Vinyl is about to learn that sometimes the most conservative ponies have the kinkiest desires...

“Yo, Tavi! I’m home!”

Vinyl Scratch tossed her mane over her shoulder as she finished hanging up her jacket on the hook by the front door. Her appreciable tits - bra-free, as she always kept them - bounced happily as they were freed from the jacket’s leather confines. Turning on her heel, she eyed the hallway leading to the kitchen hungrily.

As she stepped forward, Vinyl was answered by a low, throaty giggle. “I’m in the living room,” Octavia said, her voice floating musically through the air. Vinyl blinked, stopping in place. Tavi’s voice sounded...deeper than usual. Huskier. “Won’t you come join me?”

Slightly bemused, Vinyl changed course. She slipped her hands in her pockets and stepped into the living room, expecting to find Tavi lounging on the couch, probably reading some boring book about Hayden. What she found, though, was anything but.

A busty Octavia sat on her knees in the center of the room, a pair of massive, lap-filling tits resting perkily atop her belly. Her thighs, grown thick and squeezable, squished beneath her weight as she leaned her mass atop them, the two just barely encased in a set of tight-fitting stockings. Above them, her gigantic boobs quivered and bounced, their hefty mass wrapping tightly around an absolutely massive horsecock. It towered above Octavia’s head, rubbing against her well-endowed chest as she nuzzled its shaft around a chorus of grunts and moans.

That wasn’t even the most surprising part of it. No - what brought Vinyl’s mouth dropping open was the sheer number of cocks pointing toward her. They had no owners that she could see, but the air was absolutely filled with an army of disembodied stallionhoods, and massive ones at that. Testicles larger than her torso dangled beneath six-foot shafts, veins pulsing and throbbing as each member bobbed and swayed in the hot, musky air. Lakes of precum had pooled on the floor, each cock doing its fair share to contribute to the den of sex their living room had become.

And in the middle of it all sat Tavi herself: busty, endowed - Vinyl hadn’t known her to be a futa before now - and, perhaps most crazily of all, boasting a pair of wings and a horn. Purple shimmers of magic sparked from its tip, auras of energy encasing her own and several surrounding stallionhoods. As Vinyl watched - she could swear Tavi had grown at least a foot in height as well, her whole body growing curvier, more muscular, and jaw-droppingly gorgeous - she let out a strangled gasp of lust, awe, and fear, unsure of just how to respond to the scene of decadence before her.

“Wh-what the fuck?” Vinyl sputtered. “Tavi, what - “

“As it turns out,” Octavia purred, “creating a new genre of music seems to suffice for ascension to alicornhood.” She nodded toward a music stand pushed gently off into a corner, turned in the opposite direction to avoid some of the messier emissions of the giant cocks around it. “After I grew these” - she rapped on the bottom of her horn with a fist - “I just couldn’t resist giving them a bit of a play.”

Vinyl made a choking sound. Tavi just smiled, then gasped suddenly. Another cock was buried deep in her cunt - Vinyl could only spot its beanbag chair-sized nuts as her roommate lifted her voluptuous body off of them - and Tavi moaned happily as a head-sized bulge shifted within her torso. Octavia’s giant shaft flared, a wad of precum at least two gallons in volume splattering against the ceiling and sticking.

“Don’t you like my collection?” Octavia said. She nodded toward a thick red one. “Each one belongs to a stallion in Ponyville.” Big Mac’s, then, Vinyl’s hindbrain guessed as her conscious thoughts sunk into a dumbstruck haze. “But there’s one I haven’t been able to sample.”

“Bu - whoa!”

There was a sudden force clenched around Vinyl’s ass, pulling her forward. Vinyl grunted, gaped as Octavia’s magic yanked her toward her, even as it lewdly massaged her round, delicious rump.

“I never quite minded that you were a futa-filly,” Octavia said, licking her lips. There was a deep, lustful haze in her eyes, glinting with pleasure and purpose. Vinyl groaned, a deep need stirring deep within her as Tavi undid her belt. “But with such inspiration all around me - I just find that I can’t resist taking a look.”

The bulge in Vinyl’s panties was growing. It had already been large, but even as she reached her full hardness, it continued to swell. Vinyl panted as the fabric in her panties creaked, then finally snapped, a monstrous black slab of male-meat slapping wetly against her stomach. Her nuts were twice as large as normal, and still growing. Her whole package was encased in Octavia’s magic, she found, the bright purple energy pleasuring her as her testes sloshed and swelled with cum.

“Lovely,” Octavia purred. “You look just ready to burst.” She lapped at a glob of precum oozing down her shaft and tightened her grip on the two disembodied cocks floating beside her - Big Mac’s, from before, and...Time Turner’s? Neither could possibly be that big in reality. What kind of resizing had Octavia done? Vinyl was almost too terrified, and too horny to ask.

With a grin, Octavia pulled her hands away. Both massive stallioncocks flexed and trembled, as if begging her to return her attention to them. But she had eyes only for Vinyl’s enormous erection, which by now was reaching nearly above her forehead. With a grunt, Vinyl let out a moan of lust, her whole body tensing as Tavi squeezed her hefty, sloshing nuts. Vinyl’s hips bucked, a spurt of precum splattering against Tavi’s forehead.

“Tavi, I - “ Vinyl fell silent as Octavia held up a finger, a blush spreading across the DJ’s face as her roommate’s bounced exuberantly.

Octavia just winked. “You look simply delicious, dear Vinyl.” She gestured out at the horde of stallionhoods around them, and licked her lips hungrily. “Please - won’t you join me in my symphony?”

Vinyl swallowed. Then, her erection shuddering with unadulterated need, she nodded.

“Excellent,” Octavia said, and smiled.