Bubble Butt Bump
Within his laboratory Time Turner was always in the midst of another experiment. The walls were lined in schematics and equations, the interior cluttered with various equipment, piled up half-finished projects scattered about. The stallion scuttled past rows of stacked up books, humming to himself, dapper in his dress shirt, slacks, and tennis shows.
His eyes fell on his latest creation; an hour glass. But this was no ordinary device, not after he'd supplied a fusion of science and mysticism to it! Of course as an earth pony he couldn't exactly cast spells himself, but through alchemy he'd achieved suitable workarounds that would put your average unicorn to absolute shame! “Now, to test my theory. Oh Derpy~!”
She always seemed to be underfoot whenever he needed to concentrate; an absent when he could use her the most. Yet she was also the most faithful assistant he could have asked for. His ears flicked when the pegasus flew in from another room, almost crashing into him as he neatly side-stepped and caught her. She blinked her bright, uneven eyes. “Hello, Mr. Turner!”
“That's Doctor Turner,” he reminded and set her down. “I need your help with something.”
“Certainly, Mr...I mean Dr. Turner!” She snapped to attention with a salute, garbed in a blouse, miniskirt, and heels. Not exactly regulation, but she simply smiled, oblivious to how his eyes would dart on occasion to her plush cleavage topped by perky erect nipples that he swore would burst through her top at any moment.
“She's too sweet and innocent,” he mumbled to himself under his breath.
Derpy Hooves raised an eyebrow, her plumage drawn close to her. “Uh, so what do you need me to do?”
“Good question.” He stroked his chin and stared at the hourglass, its pile of sand at the bottom. “How about some stretches?” It was the first thing that popped into mind; some repetitive task she was used to. He'd seen her train when filling in for the Wonderbolts, and despite her reputation has surprised everypony when she put her mind to it.
“Like this?” She bent over, her bulbous breasts hanging and swaying with a subdued jiggle and smack together, almost spilling free when she reached down and touched her fingertips to the toes of her shoes.
He gulped hard. “Y-yes. Like that. Now, hold that position.” He trotted over to the device and flipped it over. It rattled on the table and settled back into place. Looking over his shoulder, he noticed that Derpy dock had raised her blonde tail high, her pert bottom and wide hips almost fully exposed, shrouded only by bubble-decorated panties which crawled up her clefts.
“Bad thoughts...bad thoughts,” he whispered and bit his lower lip. Without thinking he said, “Do the splits!”
Derpy spread her legs to the sides and lowered herself with a gymnast's grace until she touched the floor. The hourglass righted itself, and the moment repeated, seemingly in slow motion, as she snapped back to a standing position then slid down.
“Eureka! Success!” He snapped his fingers. “It seems I can set the timer and create a closed loop.”
Derpy giggled and beamed. “Glad I could help out, Dr. Turner! So what do you plan to do with it?”
“I don't know.” He shrugged. “In truth, the reward is in the experiments themselves. Although maybe it can be used to help Equestria somehow? I'll have to consider all the possibilities. Or should that be implications? Tsk, tsk.” In moments like these he was so wrapped up in his thoughts he forgot her presence entirely. He paced back-and-forth while she watched.
She toyed with her messy blonde mane. “Well, if you're busy thinking it over, I guess I'll take a bath!” Fluttering her wings, she hovered out the room, her pleated skirt sailing upwards amidst the draft to show off her barely-clad derriere.
“Sometimes, I swear she does it on purpose.” He shrugged, trying not to imagine her stripping down for her latest bubble bath. His mind's eye flooded with her delicious curves, wet and dripping after she submerged herself in the tub...
With a self-inflicted smack to his face he refocused. “No, I have work to do! And besides, she's so naïve I wouldn't be surprised if she doesn't understand how ponies are made! Maybe I'll educate her sometime...no, not like that!”
Rather than concentrate on the finer aspects of his assistant, he made entries in his journal about how his latest creation might be used. Unfortunately most of the scenarios which came to mind were nefarious; there was no end of ways a villain might use such a device to their advantage. He sighed and lamented his own genius, uncertain if he should have even bothered.
His reverie was broken when a high-pitched voice called, “Dr. Turner! Help!” Without a moment's hesitation he raced out of his lab, down the halls, and into the restroom. He skidded to a stop and his heart skipped a beat. Derpy had stripped almost completely, but was somehow tangled up in her own stretched panties, and he failed to avert his gaze.
“Just hold on.” He swallowed and steadied himself in attempt to be professional. Sure, he wasn't that sort of doctor, but he'd simply pretend this was a medical exam, disentangle her, and do his best to forget he saw her in such a compromised position afterward. Carefully he peeled the offending garment loose, touching her as little as possible in the process.
Giggling, she started to tumble backwards, grabbed at him for support, and she toppled into the tub with a splash that sent a cascade over the floor, dragging him in with her. Her bubble bath solution tipped with them, filling the waters with sticky suds that glistened and floated around them. “Oops, my bad!” She beamed at the soaked stallion. “But since you're already here, Dr. Turner, why not join me? You could use a bath, too!” She started to unbutton his wet dress shirt with a grin.
“Uh...” He blushed but couldn't bring himself to stop her. It was only a bath, right? Allowing her to take the lead, she disrobed his soggy clothes piece-by-piece, until he was also down to his birthday suit. Her eyes drifted into focus on his junk, darker than the rest of his fur, and with sudden self-consciousness he sank into the heated pool to hide himself.
“Allow me!” She grabbed a bar of soap from a container nearby, lathered up her palms, and started to rub down his lean muscles. Without thinking he emitted a soft moan, and she beamed wider, tracing down him. She waded closer, practically sitting in his lap, pressing her supple breasts to him while she worked, her wide perky nipples poking into his skin.
Perhaps she wasn't so innocent, after all? Relaxing his posture, he let her do whatever she pleased, her hands wandering all over his toned back, down to his chiseled buttocks. Nope, she'd definitely done this before!
Her tail swished and her eyes managed to lock with his. “Dr. Turner, I...I've waited so long for this. It's why I wanted to become your assistant to begin with. I read all your papers, wanted to meet you, and when you placed that ad in the paper...”
“Derpy, I.... Shouldn't we keep this professional? It feels wrong to do this with a student,” he admitted.
“Then I don't want to be your student anymore! I want to be something more.” And with that confession she sunk herself down onto his crotch. A moan ripped from her when she impaled herself on him, his half-erect mast swelling to fullness while it entered her silky folds, bottoming out when his flare struck her cervix. Her limbs and plume encircled him.
Her maw opened with a contented sigh. He took a moment to savor her softness, her body heat, certain she did the same. All this time she'd been fantasizing about him, just like he had with her. But he'd swept such ideas aside, unwilling to cross that barrier until now. It seemed so silly. She'd make the perfect wife. Gradually, the pair started to move as one unit.
Her maw pressed to his, her kisses eager but clumsy, nibbling at him. Water sloshed about them, slipping over the sides and pooling over the floor, his arms tightening around her, crushing her close to his bare chest. She swished her tail and flicked her ears, happily and shamelessly moaning, and he grunted back, it having been years since he was last laid.
Her wet tits slapped upon him with each bounce, his hands kneading into her slippery bubble-butt. She withdrew her snout with a gasp, full-face blushing, ribbons of saliva still connecting them. “I...I love you, Dr-”
He pressed an index finger to her lips with a mischievous grin. “Just Time Turner will do from now on. After all, I want to marry you, after this is done.” She squealed with a giggle, and he laughed with her, his own face dopey with bliss.
Her hands tightened around the back of his neck, and he thrust faster, harder, groaning with her, determined to push them both over-the-edge and make their union complete. He could always worry about contraceptive potions later!
She whimpered and cooed, flexed her wings to their full span, tightened around him, milking him. He wheezed, breaking the final barrier as his tip pierced her cervix, his flare blossoming out to embed itself there. “D-Derpy-!”
In answer she slammed her wide ass down, his cock hitting the slippery confines of her womb when he bottomed out. The force of her landing shook his lab, and elsewhere the hourglass tipped off the table from the impact, shimmering as it activated.
The couple screamed each other's name, his balls emptying into her slimy core in hot spurts that splashed her pink walls, and her dam broke almost in unison, a tsunami of marecum spurting into his lap and spreading in the bubbly waters. They cried out their mind-numbing orgasms and wrestled their tongues, clenching their buttocks as warmth filled them.
Neither would ever know they, and the rest of Equestria, were forever doomed to repeat this moment. Swallowed in a time loop, the hourglass falling over only to right itself again-and-again, they experienced an eternity of the same mind-melting climax.