Growing Needs

"I can't believe you of all people would do that."

"I didn't do anything they didn't start."

"Don't talk back to me," Ms. Grace snapped. She was pacing, wearing out her heels on the gymnasium floor, and squeezing her hands together. Though dressed for work in a sensible shirt and skirt combination, Mia only noticed the swell of her curves, shapes obvious against the clothes as if trying to rip themselves free. She was wearing a bra, though with the errant drip of fluid from her legs, it was doubtful she had panties on. Why did she have to act so outraged?

It'd be so much simpler if she acted as her students did and just gave in. More words dribbled from her lips, meant to demean Mia for her unintentional actions, much as she was enjoying their results, yet she paid little attention to the human. It was just a matter of time before Ms. Grace lost control of herself. Instead, Mia looked around.

The gym had become a stranger to her since the surgery. Hooves weren't really designed for indoor exercise, instead she just ran around the fields at her old home and occasionally lifted weights to keep her upper body fit. Not that she needed to anymore. Every second that she grew, her muscles compensated, sometimes too much. Already her flat stomach was dimpled with abs.

Of course, the same spread to her equine body as well. Anyone could tell she was a prime stallion at a glance, even ignoring the obvious virility of her sex. Striations ran across her form, always moving as she grew and her weight shifted slightly. The wooden floor beneath her groaned under her form, only masked by Ms. Grace's aggravation and Mia's shirt nearing the end of its short life. It constantly groaned under the strain of her growth.

Entire inches of breast size seemed to appear between blinks. That couldn't be true though, otherwise she'd be so much bigger already. Hitting her head on the rafters, accidentally destroying them just by growing even more, or she'd fill out the gym. Her cocks weren't against the idea as they kept spilling pre-cum.

"Are you even listening?" Ms. Grace asked.

"Hmm?" Mia tilted her head back to look at the human, no longer even half her size. What power did this small creature have over her? She frowned at her thoughts and ran a hand through her pink locks. Of all the abnormalities of her body, the colour was the only thing she chose for herself. For almost a week now, it did whatever it wanted, growing and seducing and fucking. Or were the last two her decision? It wasn't like she couldn't control herself anymore. She hadn't jammed Ms. Grace on a cock yet and she wanted to.

"Mia!"

"Huh?" The centaur looked down again, hands slipping from her breasts she hadn't realised she was groping, and saw her cocks nudging the lecturer, closing on all sides. Mia stepped away.

"Clearly you're in need of discipline. Drastic measures are necessary," Ms. Grace muttered, chewing on her lip, and rummaged through her purse. Mia hadn't even noticed it until then, "And these will help." She pulled out a set of metal cuffs, with a chain hooked into a loop that produced a series of clamps.

Mia restrained a laugh, "Those aren't big enough for my wrists."

"I-I know," Ms. Grace said, face turning tomato red, "That's why I've got these." This time, she revealed a bunch of zip ties, which she wove together until they could handle the centaur's size. Few humans had strength enough to rip them apart. Mia flexed, studying her arms as muscles bloomed across them; maybe she could?

"Bend down."

Mia obliged. If nothing else at that moment, she was cordial, happy enough to humour this person until the inevitable happened. God, what was she becoming that she was so fixated upon it? This woman, a teacher at the college since before Mia enrolled, was trying to lecture her and she could focus on nothing but the prospect of fucking her. It wasn't her fault, not entirely, given how close she'd come to getting off earlier. She should've fucked her new housemates that morning.

"There, feeling the weight of your actions now?" Ms. Grace asked, having tightened the restraints so the durable plastic bit deep into Mia's wrists.

"Yes," Mia said, though her cocks throbbed, drooping further as they grew. Was her teacher into BDSM, did she dominate people in private? She licked her lips, a unique tingle fluttering through her loins. Who was Ms. Grace to even think she could dominate her? "What next?"

"Next? I... what happens here doesn't leave this place, understood?" Mia nodded, "Good. Words aren't enough for someone like you. Nothing but a beast in season, looking for the nearest female to mate." From Ms. Grace's purse, a tight knot came out, then unfurled into a cat o' nine tails. She whipped it through the air, wind hissing around the many lashes.

"Shirt off."

Mia stripped her sole piece of clothing. She expected it to snap back into its former shape, given the strength of the elastic and, while it did shrink, the shirt had seemingly tripled in size. How long would it last against her and, for that matter, how long would Ms. Grace? All notion of punishment left the teacher's mind as she gawked, eyes reflecting the majesty of Mia's chest, so huge it could support a small class. If Mia held them together and she climbed into the cleavage, she doubted she'd ever see light again.

"What next, Ms. Grace?" Mia asked, an unintentional huskiness in her voice.

"Um, next is... right, yeah, next is punishment. For being so lewd in class."

"I was being lewd?" Mia feigned ignorance. Teasing this woman might be wrong, she did have authority in the college after all, but it proved irresistible.

"Yes!"

"How so?"

"You... you picked up that girl! And sat her in y-your cleavage."

"I couldn't read her tiny book from so far away."

"What about when you... when you started... orally servicing her."

"You mean when I ate her little pussy out with my giant tongue?" Ms. Grace nodded, her cheeks the darkest crimson Mia had seen on a person. Even the most hot blooded redneck didn't compare. So much of Mia's life highlighted just how big she was becoming, the fact she had casually lifted someone like that, could have smothered them with her tongue. Or fucked them better than any boy or girl with it.

"That does it," Ms. Grace said and stomped over, nostrils flaring as she closed the gap between her and Mia, then climbed onto the centaur. Dense muscles provided hand and foot holds for her, allowing the educator up until she was on Mia's back, "Let's see how obscene you are after this!" She let loose with the whips, lashing across the giantess's back.

It stung. Like a hot bar brushed along her skin, she flinched, but it didn't hurt. Not to say it didn't have an effect on her. Mia braced for the next one, back tense, and bit back a tiny moan as her nipples engorged, like they were siphoning the sensation and fuelling themselves. On the next, her cocks flexed and spat pre-cum. The sounds distracted Ms. Grace, who peered around the centaur's arm.

"I don't believe it."

Mia did. The inch-deep layer of pre that spread across the floor was just a taste as more sputtered forth, so thick and rich with sperm that it cast the normally glossy floor in a murky veil, obscuring the court lines drawn on. As sunlight bore down upon the room, vapours rose from the sludge, filling the space with Mia's musk. She checked on Ms. Grace, who seemed frozen but for the drool falling from her lip. A little more and she'd be like putty.

To that end, Mia shook her body and the teacher fell with a dense splat. She turned around, the muck slushing around from her hooves and splashing the fallen lecturer, who wiped at her face with a look of disbelief. Shadows of cocks moved across Ms. Grace, their originators blocked her from view until Mia leaned down and shoved them aside. A tremor rocked her chest at the sensation.

If she didn't fuck in the next minute she... didn't know what would happen. Since her growth started, she'd barely gone a few hours without sleeping or fucking, the frequency only increasing with her size. Her balls groaned and expanded, the leathery sack dipping into the pool, their contents eager to join what had escaped. Just touches like those affected her to such a degree. Before long, she might cum from a simple breeze or the constant sloshing of pre-cum as her hind legs impatiently trotted in place. What was stopping her from masturbating now that her cocks were reachable?

"What is... this?" Ms. Grace asked slowly, like her thoughts were travelling through a marsh. She opened and closed her hands, pre-cum squelching in her fingers. Thicker vapours surrounded her. That was why Mia wasn't masturbating. Before her accident, she'd touched herself of course, but never since then. Random orgasms would occur, but never by her hand, even after she started growing. Her own hands wouldn't measure up against the things she'd experienced.

Let alone the possibly worrying joy she took in seeing 'tiny' people impaled on her impossible cocks then inflated to sizes no human body should reach. The sight was intoxicating. She would hesitate each time, but she looked forward to it. People not even half the size of her cocks stretched around them, begged for more and got it, and came the entire time. Mia never thought herself to be a slut, but now she feared she rivalled the crudest sorority.

How many college sluts could say they ate out a classmate, in front of others, then fucked a teacher? Not many and Mia was about to join those ranks. Ms. Grace brought a quaking hand to her lips, tongue outstretched, and cleaned a finger of pre. Like an addict, she looked to the source of unforeseen pleasure even as her legs opened and more fingers dove into her clothes. Mia released her cocks and let them obscure the hopeless woman.

Was she really going to do this? It was one thing to just go with it as Ms. Grace lost herself to the pheromones, but to take charge, to demand that she give in made her no longer an accomplice to her own body's desires.

"Well?" Mia said and gulped, cocks throbbing, "Suck one."

Like a god had passed a new commandment, Ms. Grace darted to a cock and yanked it down to her lips. The head alone was bigger than her waist, its size encompassing her vision, its scent burning her nostrils, its taste already on her tongue without meeting it, while the constant throbbing beneath its leathery flesh resonated deep in her womb. And when she finally poked her tongue into the puckered urethra, lightning struck. It sizzled in her veins, her nerves tingled, but above it all was her pussy as it soaked through her underwear. A fount of pre-cum covered her face.

Nothing would separate them at that stage. Ms. Grace abandoned her dignity as a teacher, one hand crammed between her thighs, while she wrapped her lips around Mia's peak. A moan rumbled in her chest at the flavour, eyes rolling back to gaze up at the centaur. They couldn't see each other without Mia leaning over, her daunting tits overshadowing them. The teacher swirled her tongue around the dark, spongy glans.

Every speck of previously spent cum, pussy juice and sweat gathered on her nimble muscle. She lapped it up and swallowed with glee, a smirk teasing the corners of her lips while she strained her jaw, lips and teeth dragging along the tip. It took several attempts of her sliding back, then pushing forward, but it entered her nonetheless. It always did. Smaller people than Ms. Grace had taken more.

"How is it?" Mia asked, reaching up to fondle herself. Each time she pulled her boobs apart, she was greeted with the sight of her professor, lips pushed to an unnatural shape around her cock. Stretched like that, Ms. Grace couldn't swallow, saliva escaping through tiny openings between her lips and the spined horse cock. The first row of nodules slid past and hooked into her gums. Ms. Grace moaned and gurgled louder.

"Thought so. I can't believe you were trying to punish me. Now look at you," Mia held her tits apart, meeting the woman's eyes as they gradually pushed onward, "Sucking my cock like a... like a slut."

A shiver ran through Ms. Grace at the word. She gurgled a response, prompting a moan from Mia, who stepped forward and pushed the teacher onto her ass. Led by her lust, Mia shoved until the human was against the wall, never ceasing her masturbation, even as the centaur used the barrier to push harder. Spit and pre-cum lubricated the shaft as it slid across Ms. Grace's frantic tongue and into her throat. She swallowed around it, another ring of spines slipping in.

Wetness covered the first two feet of Mia's shaft. More slid in every second, a ceaseless onslaught as Mia pumped her hips, savouring the teeth and lips and tongue as they kneaded and suckled and writhed on her cock. The other two pushed out along the wall, pressurised spurts of pre-cum escaped to further coat the floor, while Mia bucked her hind legs to rub her balls against the slimy surface. She dug her fingers deep into her tits, using the joints to pinch and pull on the nipples. Even for her gigantic frame, they were massive; easily the length of her ring fingers.

"Just a slut," Mia said with a thrust from her rump, earning a delighted choke from the trapped female, "You're not a teacher anymore, just a cocksucker. A horse-cock sucker. I'm your student, you know? We're not really hidden here either, someone could walk in whenever and see you gagging on one of my dicks like a proper whore. But that's what you want isn't it? To be my whore?"

Ms. Grace jerked her head up and down, barely moving with the supple rigidity bulging from her throat and chest. It was enough for Mia to jerk forward.

"I knew it," the centaur cooed, tail swishing and rubbing against her swollen sack, "Just like everyone else, a convenient sleeve for my cocks."

Another moan urged her to push deeper. The bulge extended to Ms. Grace's stomach.

"Nothing but a slut for my horse-girl-cocks."

Ms. Grace lunged at that. Her belly protruded as it travelled down her body, the flared tip devoured her thighs, hiding the woman's sloven juices. Flat networks of blue veins travelled along her flesh, overshadowed by Mia's gnarled vessels that distorted her shape even further.

"Can you even breathe? Not that you care. All that matters to you are my cocks."

The words took their desired effect and lured the once obstinate teacher pushed off the ground to impale herself fully. She pushed off the wall until her tip toes couldn't reach anymore, leaving her suspended by Mia's cock. It twitched, bucking the woman and sliding her just a little deeper. No matter how elastic her flesh, without proper assistance, she was stuck on not even half the centaur's cock. It was an awkward position, as Mia was just beyond her reach.

"Look at you," Mia groped her tits harder, trying to feel her pecs through them and failing no matter how she manipulated them, "You were so eager you got yourself stuck on my dick. I wonder if I'll ever go soft with you like that. What if I just spent the day with you as my cocksleeve? No one would help you. But..." She hunched over and grabbed the human, hands encompassing her hips and torso easily.

She's so small, Mia thought as her fingertips covered the human's curves. That wasn't true. Ms. Grace was above average, she knew that, but standing over her now, with a cock buried deep, and her hands all but smothering the woman made her seem puny. Fragile. Like nothing more than a sex toy.

"My personal fleshlight," Mia said, which signalled a shudder through MS. Grace. Her whole body vibrated, in turn causing another flex in Mia's prick. It throbbed fatter until the woman's blazer exploded in a shower of buttons, revealing her disfigured torso, "Oh fuck, take it." And with that, Mia yanked her closer and shoved when Ms. Grace disappeared under her barrel, forcing more inside until she couldn't push any further. The teacher took up the role and hooked fingers into the fattening veins and pulled.

"That's it. All the way. To my ring. Then my sheath. What does it smell like to you? Is it melting your brain? Making you cum? Fuck, my other cocks need to fuck so bad too. But you wouldn't let me. That means you'll have to take responsibility. Oh god, I'm gonna fuck you with all three of them." On cue, muffled shrieks of delight reverberated through Mia's shaft.

Without doing the minimum of sucking an orgasm from Mia, the tutor pushed back. Every inch of the shaft inside her was dripping with lubricant, which made the retreat smooth, until the centaur caught her.

"What are you doing?"

Ms. Grace's eyes rolled to meet hers, then fluttered as she was yanked away to the fringe of Mia's reach, then slammed back.

"I'll fuck you with them when you finish making it up to me," Mia said.

She was like a teenager discovering masturbation for the first time. No sense of rhythm or thought for stamina, just a horny centaur and her sloppy sex toy. The fact it was just one was a disappointment, however she'd make do. Or more. Mia let go and shoved her other two shafts against her 'superior', then hooked the human's arms around them.

"Hold on tight," Mia ordered, her teacher's muscles tensing in response. As she slid her to and fro now, her arms offered stimulation for the dry members as well, though it wasn't much. Kicking a hoof, pre-cum splashed high and landed all over the sandwiched instructor. Her grip didn't slacken as she was used. While the pleasure couldn't hold a candle to what Mia had experienced before, her pent up balls gurgled and her cocks throbbed and leaked in their appreciation. It took several attempts but Mia found a rhythm between her hands and hips as she fucked the teacher.

Pleasure burst in false eruptions. Like a volcano awakening from its slumber, pre-cum filled the space, her musk saturated the air, with more leaking faster as the explosion neared. Mia used her biceps to knead her tits through her shirt, moaning at how it strained more and more around her frame. She couldn't wait for it to give in. When? In the middle of class or the street? During sex?

She hoped for either of the former. That announcement to the world and herself that she was always growing, her body more voluptuous, taller and stronger, more virile and heady by the second, would never go forgotten. So many would witness, record and share the sight of her shirt ripping apart and her car-sized tits slapping against her belly in their freedom. Hopefully they'd record the orgy that followed.

"Oh fuck!" Mia cried and jerked faster, muscles rippling along her arms. Ms. Grace became a blur on her cock, the only sounds from her were variations on thick, juicy gags as her uvula was crushed against by Mia's girth. Row after row of spines entered, then pulled on her flesh as they exited, adding still more pleasure to both. The giant prick slammed against the wall harder with every thrust.

"Gonna cum, gonna fucking cum inside you," Mia mewled, then gasped as stronger vibrations ran along her prick from her teacher-turned-cocksleeve's orgasm. Her next thrust crashed against the wall, tremors rocked the building, and again on the follow up. After three more, Mia's balls swelled across the floor and helped push her forward. The barrier caved and the bulge of Mia's cock, wreathed in her teacher's body, surged through. With the others so close, they squeezed through as well.

Ms. Grace's hands disobeyed and shot to the hole created. She held on for dear life as Mia's hands were left to grip only her stretched out skin, while more and more cock entered. Mia reared back, as the first wave of semen filled out her sheath, and buried her hooves in the wall. Her jizz extended into the phallus proper, Ms. Grace's lips slid past the medial ring and down to the base, then over her sheath. The head flared and locked itself inside, refusing to let even a single drop escape.