Just a little something I whipped up real quick by request.

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"But Daaaaaaaaaaaaaaaaaaaaaaad!" Diamond Tiara whined, carefully employing father-control technique number three: forelegs shoulder length apart, face scrunched in a pout, tone starting low and gradually rising. It was one of her oldest and most time-honored tools, and rarely failed when Filthy was being stubborn about her bedtime or dessert. This time, however, the elder stallion wasn't buying it.

"No buts, young lady. I'm your father and you will do as you're told."

The filly sat down heavily on her well-padded butt, crossing her forelegs angrily and looking away. 

"I don't need to do it, daddy! I feel fine, and it's all gross!"

An equally uncompromising glare met her, and the filly flinched internally - he really wasn't going for it. "Diamond Tiara, it's unhealthy to keep your magic all pent up,and you haven't released yours in over a week; don't lie, I've been keeping track." The younger pony opened her mouth to reply, but Filthy Rich kept right on going, not waiting for the inevitable rebuttal. "Besides, even if it wasn't unhealthy, you're an earth pony, sweetie. It's our kind's job to bless the land. That doesn't change just because we happen to have a bit of money. I wouldn't give two bits for an earth pony who thought they were too good for the earth!" 

"Easy for YOU to say," Tiara grumbled, still not looking her father directly in the eye. "YOU can just let it out through your hooves, right into the soil."

Filthy Rich sighed, his stern tone temporarily fading as he knelt next to his beloved daughter, nuzzling lightly at her neck. "I know, honey, I know. I know it's embarrassing. But your magic just... works a little differently than normal. It's still good, solid, reliable earth pony life magic; it's just... a different kind of life magic. And it's still important to let it out every now and then, or else it can build up inside you too much and become unhealthy. I know it seems really strange, and I know you don't want anypony else to find out, but you still have to do this. And something tells me that once you're a little older, you'll even start to enjoy it." 

Diamond Tiara sighed, curling up into a ball ball on the floor and examining a hoof with idle disinterest, but the tension had left her shoulders. Recognizing the sign, Filthy waited patiently for the little filly to swallow her precious pride enough to say the words. When she finally spoke, he barely heard her, but the words were enough. 

"Yes, daddy..."

One short trudge to the upstairs bathroom later, the recalcitrant pony found herself staring at an impressively unimpressed frown in the full-body mirror closest to the bath. Any regular examination of her form would show only that of a fairly ordinary earth pony filly, generous though her rump might be. Concentrating, Diamond Tiara reached down within the depths of her very soul, slowly relinquishing the death-grip she held on her own latent earth pony magics. 

One brilliant flash of light later, the dimensions of the room seemed to... ripple, for just a fraction of a second as reality rewrote itself. The change was quick, as it always was, only a momentarily sense of discomfort flooding her before passing as quickly as it came. Diamond Tiara's groin grew, and grew, and grew, and despite the filly's familiarity with the sight, her eyes bulged at the scope of the change this time. Her father had been right; she had held back far too long this time. With the magic finally free of its restricting confines, it bulged forth obscenely, powerfully, quickly growing nearly as large as Diamond's entire body. Though the change had taken only a moment, Diamond Tiara's own surprise took much longer to fully work itself out. 

Sandwiched firmly between her body and the floor, a massive, veiny, flaring purple mare cock was already drooling a heavy puddle of precum on the spotless tile floor.

Diamond Tiara winced, taking in the sheer size of her member this time. It was certainly as large as she'd ever seen it, enormous softly furred testicles easily reaching the floor even as she stood. Bringing her hooves down to her stallionhood, she found she couldn't even reach completely around it, hissing at the pleasurable sensation of her warm hooves against the incredibly sensitive skin. The scent of her own heady precum was already filling the room, completely overpowering the lemony scent of freshly-cleaned surfaces. The sweet smell seemed to sink into Tiara's mind, the full weight of powerful breeding instincts demanding the fertile young pony sate her needy flesh. Beneath her, she could feel heavy testicles churning, the pearly white cum desperate for release.

Tiara obliged it. Leaning forward, she balanced against her own massive prick, the thick rod easily supporting her weight, and began to rub up and down as best she could at her hot, throbbing cock. She couldn't hold but so much of it, but gave her best try despite, improvising by rubbing her entire body up and down along the top of the pulsing shaft. She was rewarded by heavy twitch, another thick load of precum oozing out to stain the immaculate white tiles, but it wasn't enough. Not nearly enough.

She allowed her mind to wander. The images came freely, her newly hyperactive hormones doing wonders for her imagination. 

Snips and Snails, staring wide eyed at her gargantuan shaft, almost bigger than the both of them put together, and then shamefully fleeing in embarassment at their own pathetic displays. She groaned, enjoying the thought more than she thought she would.

Silver Spoon was next, her ever-dependable best friend in pure awe of Tiara's endowment. Spoon trembled, dancing absently from hind leg to hind leg as she stared in unabashed lust. Slowly, hesitantly, the silver-maned filly asked if she could touch it, veneration in her voice. 

Diamond smiled, nodding. What were friends for, after all? Of course Silver Spoon could touch her. She deserved it. If she really liked Diamond's cock that much, then she could worship it all she wanted.

Miss Cheerilee, that whore, licked her lips as she tried in vain to rally the class, unable to tear her eyes from her student's throbbing rod, the supposedly-chaste teacher's marehood visibly twitching any time she turned away. Unable to tear the school's riveted gazes from Spoon's display, the bespectacled filly now moaning openly as she humped at her long-time friend's shaft, grinding her soaked little pussy against the tower of cockflesh. At last, the teacher's resolve ended, her true colors showing as she buried a hoof between her legs, frantically playing with her clit, as fully engrossed in the show as anypony else.

Diamond Tiara's breath hitched in her throat, her entire body a frenzied temple of friction as she stroked herself to the fantasies playing out in her mind's eye. She was close now, so close. Her cockhead flared, the solid flesh on the verge of orgasm, hooves schlicking loudly up and down under the lubricating layer of her own precum-coated dick. It wasn't enough, she realized desperately. She needed more. Just a little bit more. Just... a little... bit...

Brilliantly, vividly, the images jumped once more to her mind unbidden. 

The Cutie Mark Crusaders, crying out in wanton, rapturous joy as they rode her. Sweetie Belle and Scootaloo's faces buried in her heavy balls, licking for all they were worth, the two blank flanks finally proving themselves good for something. Applebloom sat atop her mistress's dick, crying out in desperate need as she worked her tiny slit in vain against Diamond Tiara's engorged cockhead, the prick far too large to fit inside her even despite her best efforts. Even so, the farm pony did not relent, keeping her little whore cunt pressed tightly against Diamond's cockslit, so desperately eager to catch any cum that might escape, needing it inside her, needing Diamond's spunk more than she'd ever needed anything in her life. Diamond screamed out in triumph as she felt the cum surge upwards through her shaft, blasting into her rival's cunt, completely flooding her womb in a single massive ropy strand before jerking free to cover the farm pony's body in a thick coating of horse cum. 

Applebloom was going to have her foals.

Tiara's scream matched the one of her fantasies as the most powerful orgasm of her life ripped through her, her massive prick twitching and jerking as it painted the room with lance after lance of thick, warm filly spunk. 

Several long, long mmoments later, a thoroughly exhausted Diamond Tiara collapsed heavily to the floor with a sigh, sleep already creeping into the corners of her consciousness.

That night would mark the first of a long, long series of recurring dreams.