The Change!

Spike nearly dropped the groceries he was carrying when he came within earshot of his and Twilight's home. He stopped for a brief moment and closed his eyes. "Not again..." Then he gripped his bags and hot-footed it home, racing past more than a few worried ponies who'd been brave enough to venture close to the Library to see what in Tartarus was going on!

As soon as he'd crossed the threshold, he let the bags fall and then ran upstairs. It was just as he'd feared: Twilight was in full 'mad scientist' mode.

Again.

The first thing he did was to go over to the record player and scratch the record off. The eerie organ music stopped. Twilight stopped in mid-cackle and spun around to face him. "Spike!" she cried. "I was setting a mood!"

Spike sighed and walked over to her. "I can see that." He held out his arms. "Give me the cape." She pouted and removed the high-collared, black and red opera cape and sheepishly handed it to him. He then walked over to the window and looked down at the ponies gathered outside. "You're scaring the normals, Twi." He looked back at her. "What kind of scheme is it this time?"

Her smile widened to such a degree Spike took an involuntary step back. "It's quite simple, Spike!" She pulled her shirt open, then took her breasts in both hands and squeezed them. "See these?! With my knowledge of magic and alchemy, I'm going to make them HUGE!" As the little dragon was struck speechless, she turned around, pulled up her skirt, and continued. "And I won't stop there! Stallions just love a big, fluffy butt! Mine will rival Pinkie's, or even Rarity's!"

Spike took a moment to wipe the drool from his mouth, and finally managed, "Buh...but why do you want to do all that?"

She cocked an eyebrow as she looked over her shoulder at this ludicrous question. "Why, for intercourse, of course!" She let go of her skirt and started pacing again. "I'm tired of all the bimbos in this town like Rarity, Fluttershy, Pinkie, and...and...Derpy hogging all the male attention!" She rounded on Spike, leaned down near his face (too near!), and exposed her boobs to him again. "Derpy! Are her breasts that much bigger than mine?!"

Spike took the cape he was still holding and strategically placed it in front of his crotch. "I...I can't say, Twilight..." He then wiped the sweat that was forming off his brow. "Is...it getting hot in here?"

But 'Oblivious' Twilight took absolutely no notice of his discomfort. She reached down, grabbed one of his hands, and brought it up to her tit. "Feel this! Isn't it soft? If you weren't my dear brother, wouldn't squeezing my breast make you aroused?"

With an effort, the stiff dragon cleared his suddenly dry throat, while continuing to knead his sister's boob. "Whoa...y...yes...I would be..."

Twilight suddenly straightened up, freeing her tit from his grasp, and looked off into the distance, growing thoughtful again. "But just imagine how nice they'll be once I've enhanced them..." She spared Spike a glance, who was by now sweating profusely while staring at his hand. "Are you alright, Spike?"

He couldn't look at her. "Umm. Yeah, Twilight. I'm...fine."

She beamed at him. "Good! Because I want to get started right away!" As she made for the stairs, she stopped and added, "Gather all the books you can find on 'body transformation' and meet me in the lab! I have tons of research I need to do!"

He finally looked up at her. Her breasts were still exposed, and the back of her skirt had gotten caught on her belt, showing every bit of her sweet, round ass in her tiny white lacy panties. "I'll...be right there, Twi..."

She smiled again, totally unaware of her state of déshabillée, now that she was in complete 'research' mode. "Don't keep me waiting, my Number One Assistant!" Then she turned and hurried down the stairs. As soon as she was gone, he dropped the cape, exposing his diamond-hard cock, and took a steadying breath as he tried to free his mind of the sexy images he'd just endured. Without another word, he made straight for the bathroom, jumped in the shower, and turned the cold water on.

Full force.

"Ahhh! Ahhh! Ahhh! That's it! Deeper, stud! Fuck me harder!" yelped Applejack. She was on her stomach with her shorts ripped off, back arched, and holding her ass cheeks open while the stallion behind her plunged his meaty cock in and out of her ponut. "Oh mah LAWD Ah luv a cock in mah ass!" she squealed. She could feel every vein and knob of his dick as he fucked her with wild abandon, her eyes rolled back in her head and her tongue lolled out. "Don't yew stop!!"

All around her, the other mares and stallions were lying completely exhausted in piles; Pinkie was covered in cum, resting peacefully with two cocks across her smiling face as she idly sucked on one like a pacifier; both Fluttershy and Rainbow had been fucked until their partners had passed out; Rarity was holding up a makeup mirror to her face as she sat between her two satisfied paramours. After fully draining both their ballsacks with mouth, pussy, and ass, she was making the vain attempt to look presentable once more. Closing her mirror with a snap! she smiled, sighed, and gave up. After such a session, there really was no point in trying to hide what had been an extremely fun and satisfying time! She sighed again, wishing such times could happen more frequently.

As she sat there musing, Applejack gave a great cry and came, her entire body seizing up as the guy behind her buried himself to the hilt and came himself, his eyes rolled up as he jerked and pumped load after load of cum into the blonde's tight ass. In a brief notion of pure greed, Rarity licked her lips as she watched them, then considered taking him on herself after he'd finished with her farmer friend, for Celestia only knew when she'd get the chance to have this much fun again! But as he pitched forward and fell limp on top of AJ, she knew they were both down for the count. That's the problem with stallions; big dicks, no real endurance, she thought to herself.

If only there was some way that could change...

Meanwhile, Twilight busied herself in her lab; setting up instruments, putting on her long white coat, and adjusting her blackboard. She was in the middle of perusing a few tomes on the basics when Spike finally made his appearance. His arms were loaded with books as he struggled down the stairs, taking them one careful step at a time. He looked up at his sister as he reached the bottom and blew a brief sigh of relief to see she'd put on a concealing lab coat! In all the years he'd known her, he'd never seen her so distracted to the point she'd lost all modesty around him, and he sincerely hoped this would not be the start of a trend.

"Here's everything I could find you asked for, Twilight," he said, taking a moment to wipe his brow. Those damn things were heavy! She looked up and beamed at him.

"Thank you, Spike! I can't wait to get started!" She was so excited she got up to hug him, which was of course when Spike noticed she'd forgotten to button up her coat, so her tits were still visible. He swallowed as she bent down and enfolded him in a booby hug. She then straightened up with a giddy giggle and grabbed the first few volumes in her magic and in her arms, took them to her table, and began reading them all at once.

Spike shook his head to clear it of all impure thoughts, then said, "I know how you get when you're studying. I'll go make us both something to eat." She merely grunted at him, her attention fully on her books, so he knew she hadn't even heard him.

About an hour later, there was a knock on the door. When Spike went to open it, still clad in his apron, there were all their friends, looking quite tired but satisfied, in various states of undress. Spike stared at them all, sighing inwardly. Wearily, Rarity spoke. "Is...Twilight home? We wanted to return her picnic blanket, and thank her for the privacy shield..."

Just as the little dragon was about to answer, there appeared Twilight behind him, munching on a big burrito. She frowned at them, and said, "Oh. It's all of you. I suppose you all had "fun" without me?"

They all had goofy smiles of one sort or another on their faces, but Pinkie was in the "worst" shape of them all. She was being supported by Fluttershy, with one of the sleeves of her mini-top falling off, and her knees bent inward in an awkward position.

Her eyes were unfocused, and she kept muttering, "Cocks...cocks...so many, tasty, tasty cocks..."

"I suppose that was a stupid question," finished Twilight.

They all blushed, but Rainbow took the lead this time. "Twi, I'm really, really sorry I made fun of you! I promise it won't happen again!" She laughed nervously and placed a hand behind her head. "It was just...the heat of the moment!"

Applejack took up the explanation. "None 'o us woulda acted like that if'n it weren't fer the daggone dry spell we've all bin havin'!" All the mares except Twilight gasped and turned to Applejack. Even Pinkie was aroused from her stupor at this news.

The fashionista was the first to respond. "Wait...you have been experiencing a 'dry spell,' Applejack?!" The farmer nodded sadly.

"Big Mac has bin outta town for the past few weeks visitin' relatives. It's just bin me, Granny an' Apple Bloom!" All the mares crowded around her and expressed their sympathy, but Twilight was still out of the loop.

They all turned to her as she held up a hand and said, "Hang on: am I missing something? What does Big Mac have to do with her 'dry spell?'" When they all simply stared at her with flat expressions, her face changed from puzzlement to vague understanding. Then her eyes flew open wide and she slapped a hand to her mouth as full realization dawned. After a moment, she found her voice. "You don't mean...you...and Big Mac...you two...NO!"

"Have you seen her brother?" asked Rainbow, rather rhetorically.

Twilight spluttered, "W...well, yes! Of course! But...but..." she finished lamely.

Applejack waved a hand. "Ain't no 'buts' about it. That man's got the biggest cock in Ponyville, an' Ah shore ain't gonna pass it up!" Her eyes became dreamy and unfocused. "An Lawd a mercy, does he know how ta use it!"

All the other mares sighed and nodded.

Spike had become very quiet.

She took a second look at them as she spoke, then her pupils shrank to pinpricks as she spied the blanket. "Is...is that the thing you all have your...(gulp) fluids on?!"

Applejack looked down at the blanket she was holding and said, "Well, yeah, Ah suppose..."

Twilight bared her teeth, and whispered, "Drop it..."

AJ cocked an eyebrow. "Excuse me?"

"Drop it, I said!!" Applejack startled and did so. "Now, stand back!" cried Twilight. Quickly, she reached behind herself and produced a pair of goggles which she immediately donned, then grabbed Spike and hugged him to her chest, his head facing the offensive object. Pumping his tail up and down like a lever with her other hand, which caused his head to click open and shut, sparking like a Zippo lighter, he finally caught flame which shot out about ten feet! With gritted teeth, she directed the flame at the soiled blanket until it was nothing but a pile of cinders! She then snapped his mouth shut, cutting off the flames, and set him down as she caught her breath.

Spike looked up at her, tendrils of smoke still emanating from his jaws. "Really, Twilight?"

She took off the goggles and wiped her brow. "It needed to be done, Spike."

All her friends were struck speechless until Applejack finally spoke up. "Ya coulda just washed it, Twi."

The librarian stared at her as if she'd gone mad. "No," she said in a low, dangerous voice. "No, I couldn't have."

"Okay: Explain it all to us again exactly what you're doing, Twilight?" asked Rainbow. All of them were seated down in the basement laboratory in front of the purple alicorn, as she stood before her blackboard. Upon it were charts and hand-drawn diagrams, which could have been written in ancient Ponish for all the sense they made to her friends, but which Twilight was excitedly pointing out.

"It's actually quite simple!" She turned once again to her diagrams. "Once I've figured out the exact spell, I will be able to enhance myself physically and emotionally! I will no longer be the shy, nerdy bookworm that I know you all think of me, but an inexorable, implacable, seductress!" In the stillness of the room, a cricket chirped.

Twilight sighed. "I'll be a hot bimbo."

"Ohhhh..." they all said at once.