Looking straight ahead at the whiteboard, I tried to keep quiet as I rubbed my thighs together, enjoying the sensation of my little package being squeezed between them until my cocklet began to peek out from my panty-clad sheath. There were only a few of us in Mr. Reed's advanced calculus tutorial, and while we all had our heads pointed forward, the rest of the students were focused on the writing, rather than the writer.
                To each their own, I suppose. They were chasing extra credit, while I was chasing Mr. Reed. Don't get me wrong, I'm not just a pretty face. For one, I'm a gorgeous little bunny, but more to the point I'm smarter than people think, otherwise I wouldn't have been able to qualify for this tutorial, or keep up while spending most of my time salivating over the towering canine.
                I suppose I better paint you a little picture, so you can keep up with this narrative. I'm a sixteen year old bunny named Alex, although I've been going by 'Lexy' (or 'LexxxyBunn' online) ever since I jumped on the cross-dressing band-wagon when it became all the rage about two years ago. In case you've been living under a rock, the whole idea of the trend was that a lot of boys these days went around in skirts and high-heels, while a lot of girls had switched to sneakers, t-shirts and loose-fitting jeans.
                At first everyone had tried to keep up with the trend, but as it got more and more elaborate, only those who could pull it off stuck with it. And I could definitely pull it off. I've always had a svelte build, and bunnies to tend to have pronounced hips and well-developed thighs, so I had a lot to work with. I generally covered up as little of my snowy-white fur as I could get away with, and today was no exception. I had on four-inch heels (to help really show off my thighs and ass), a pleated skirt which could have passed for a part of a school-girl's uniform if it hadn't been so short that it barely covered my panty-clad ass, and a pink tank-top so tight that my nipples tended to poke through when I was in the mood (like, for instance, when I was salivating over the sight of  a muscular canine ass, like I was right now).
                I was really proud of the tank-top because I did the appliques myself. Across my flat chest (some of my friends wore padded bras, but I figured I had enough curves where it counted that I could 'flaunt flat') I had the standard 'I' followed by a glittery heart, which in turn was followed by a canine paw-print and... well, let's just say a tied-up piece of rope. The pink lipstick I wore matched the highlights in my feathered blonde hair and my ears were short enough that they stuck up straight through the whole mess (although I did tend to flick them back when in a subby mod).
                Now, you're probably wondering what kind of school this is when I could get away with showing up to class looking as slutty as I possibly could? Well, it was a fairly normal one. A good, private school that liked to boast of being progressive, and in the current social climate that meant tip-toeing around students that seemed to fall into the LGBTQ category. Now, despite what some people (mostly the ones I turned down) have scrawled in both the boys' and girls' restrooms, I'm not a fag. I'd been with plenty of girls, especially when I was getting into this whole CD business and wanted to soak up as much femininity (literally and figuratively) as I possibly could. But ever since I got this crush on Mr. Reed I've been craving cock, because when I was getting it I could at least pretend it was his. His continued refusal of my advances was making a lot of canines around the school very happy, since none of them knew (or would care) they were just Reed-substitutes.
                Ah, we get to the source of my frustrations. Sean Reed, the towering Great Dane dutifully lecturing his prize students had so far brushed of every subtle attempt on my side to signal my amorous intentions. This irked me, since I overheard from people who knew the young teacher from his even younger days, that he used to swing both ways. So I had long since gone past subtle, tried flirtatious, and was now openly slutting it up for him (hence the "I love canine knots" top), which was beginning to annoy the dog of my dreams. At this point, I didn't care. If we couldn't have a passionate romance, I'll settle for a vigorous hatefuck. I knew that if I could just get what I suspected was a truly glorious doggy-dick (they don't make pants loose enough to hide that bulge!) between my bubbly bunn-bunns, he'd realize I was the best thing that ever fell into his lap. Or bent over for him. Or lay on a bed with my ankles cuffed to the bed-posts behind me. I've built up a pretty long 'to-do' list for him over time...
                Just the sight of him was making my little cock leak into my silky panties. He was well over six feet tall, not heavily muscled although he obviously worked out, his white coat covered in messy black splotches. In fact, one of my failed attempts at seduction had consisted of dyeing a similar pattern over my fur, then commenting on how well we went together as I brushed up next to him. It had failed, and as he walked away unfazed, I stormed down to the yard, picked up a Dobie that I knew was always DTF and dragged him to the boys' room so he could fuck the frustrations out of me. 
I didn't even mind that he'd filmed the whole thing on his phone, and had even considered asking him for the video so that I could send it to Mr. Reed and show him just how good my ass looked with a nice, fat knot lodged in it. I didn't actually do it, at least not yet.
I managed to make it to the end of the class without creaming myself, even though my pretty little panties were a soggy mess by now, although I didn't mind. Anyway, dogs were supposed to have amazing noses, so a little natural fragrance couldn't hurt, right? The other students had left, leaving me and Mr. Reed alone. He didn't seem too pleased by the prospect, probably because me sticking around after everyone has left usually meant I had another cleaver plan to get into his pants.
I put a little extra swing into my walk as I sashayed over to his desk, swaying my hips as my heels clicked with every step. He was looking, although I could tell he was trying not to. He really was a good teacher, dedicated to his job and his students, but knowing that only made me want him more! I tried to put him at ease, asking a few questions about today's lesson, and trying to come off as an attentive student as I put my plan into motion. He was standing next to his desk, obviously eager to get away from me, so I had to act fast.
I 'accidentally' knocked over a pen from the edge of his table, and with what I consider was an adorable 'Oops', turned around and bent over to pick it up. Now, I mentioned earlier that my skirt only barely covered my ass? Well, that was assuming I was standing up. Bent over as I was it rode waaaaay up, and considering my fluffy little tail was also raised as high as it would go, that left nothing covering my perky butt other than my thong, which wasn't doing a very good job of it. After a few seconds of that I faked a stumble, hoping he didn't realize how comfortable I really was in heels as my ass fell back until it bumped against a hard black-and-white wall. Bingo! His height meant that even in heels my butt wasn't rubbing against his crotch, but my tail was, so I made sure to give it a few twitches.
"Oops, sorry about that, Mr. Reed..." I said as I slowly straightened, while still leaving my rump pressed against him.
"Mr. Williams, what are you doing?" he said and I almost groaned in frustration. I hated when he got formal like this!
"Well... " I cooed, my back arched so that my rear was still trust out at him "... I know it's tradition to bring your teacher an apple, but I was hoping you would accept a nice, fuzzy peach?" I finished, giving my rear a little wriggle. Everyone had their breaking point, and I was desperately trying to push him past his.
I heard him let out a long breath through his nose, which usually meant he was getting his composure back. For me, it was the sound of failure. I could see he was tensing, getting ready to leave, and I was so horny I briefly considered literally throwing myself at him when I felt him grip me by my arm. A shudder ran through my body at the contact, although he didn't look very happy.
"Come with me." He said, and I could see the tension in his jaw. As he led me through the halls, I wondered if he was taking me to the principal. I doubted he was even still in his office, since the calculus tutorial began after class, and by the time it ended the school was almost empty. We stopped at the stationary storeroom and I just stood there speechless while the man of my dreams fished a key out of his pocket. He gently ushered me into the small room with its shelf-lined walls before turning around and locking the door after him. 
Dogs had sharp noses and rabbits had sharp eyes, and the first thing mine noticed was that unlike pretty much every room in the school, this one didn't have a security camera. My heart leapt into my throat and my tail began to tremble as I felt my tail-hole wink in anticipation. This was it! He'd led me to away from prying eyes and locked the doors behind us! There could only be one reason for that...
"Alex..." he began, and not even his use of my given name could turn me off at this point "...why do you keep doing this? You're bright enough to know by now that it won't get you anywhere."
No, no, NO! Not a lecture, not when I was sooo close! I had to think fast, I had to make this happen!
"I know, but... why? Don't you think I'm pretty?" I said, switching to a shy, vulnerable posture. Check-mate, hot dog! Now he can either admit to being attracted to me, or lie and hurt a student's feelings at the same time.
"You know it's not that..." he said, calming down a little.
Yes! I knew he's got the hot's for me! And if my eyes don't deceive me, those pants are getting snugger and snugger in the crotch!
"But even if you weren't underage, I'm your teacher. Do you have any idea how improper it would be for me to have relations with a student?" he asked, and something inside me snapped. I figured if I went all in, he would too. Quite literally, with any luck.
"What-what if you weren't my first?" I asked, an idea forming in my mind.
"What do you mean?"
"I mean, what if I've already had other teachers?" I said, and I could tell his breathing was speeding up. A good sign, especially since in this tight space, every breath would carry the scent of horny bunny. "Hell, you're probably the only member of the faculty that's been missing out..." I said, taking a step closer to him, letting my voice get husky as I spun the scandalous tale.
"I've let all the others have me. The females would ride my face while the males took turns riding my rear. Bunny ass after class. Seriously, you should take a black light into that teachers' lounge, it'll look like a Jackson Poll-" I stopped when a heavy paw suddenly landed on my shoulder. Fuck, it was big...
"On your knees..." the towering canine said, his voice low and level as he firmly pushed my shoulder down. Not that I needed pushing. I knelt in front of him, my head craned back as I looked up at him, holding my breath. The sound of a belt being unbuckled snapped my gaze right in front of me, in time to see Mr. Reed pull down his zipper and slide his pants and his boxers down his legs.
I was doing my best not to drool at the sight of his package. His cock was only a few inches out of its thick sheath, and already it looked massive, with two heavy-looking balls (one black, one white!) swinging bellow it. I could just imagine those beautiful orbs emptying their huge load into me, all slick and shiny after a good licking as they twitched and twitched...
At this point I didn't need to be told what to do, having been prepared for this scenario by countless wet dreams over the past couple of years. Placing one trembling hand on a muscular canine thigh I gave him a long, slow lick from his sack all the way to the tip before closing my mouth over his emerging cock. A little squirt of doggy-pre was my reward, and I gulped it down instantly, eager for more.
Fuck, if he wanted a submissive little cock-slut, why didn't he say so? A few months back, I'd showed up to his class wearing a black leather dog collar and asked him if he liked my new look, and all he said was that I looked fine! Well, no use crying over spilt milk, especially when there's a throbbing canine cock that needs milking.
I felt his hand on the top of my head, and my ears immediately flicked back submissively as he gently but firmly pushed me until my button-nose was brushing against his sheath, more and more of that hot doggy-dick sliding out and into my eager mouth. Well, it would be in my throat soon enough, but I wasn't concerned, having gotten rid of my gag reflex some time ago.
"So, Lexy, is it?" he asked, and I could feel my own cocklet leaking into my panties as I looked up and met his eyes.
"Mmm-hmm." I hummed into his cock, not wanting to take my mouth off it for even an instant.
"Ugh, fuck!" he groaned, sending another spurt of pre down my gullet as he pushed my face into his crotch.
I definitely didn't mind the possessive treatment, after all the time I spent trying to get his paws on me. Mine were busy wandering over that muscular frame, as I slid one hand up and down his flexing thigh, while the other one began to fondle that plump sack. God, those things were heavy! I wondered if he intended to empty them down my throat before pumping a load under my fluffy little tail. I wasn't even considering the possibility that he'd dragged me in here like this just for a quick blowie. I was gonna get a load of puppy-batter up my eager little ass if I had to jump on his cock!
Still, I didn't mind a nice cock down my throat, and this one was the nicest I've ever had. And I give great head, if I do say so myself. Most guys are reluctant to let me at first, since even though my incisors are only long enough to be cute, they still look a little worrying. But those males brave enough to risk them always keep coming back for more. I noticed his knot plumping up so I immediately pulled his sheath down, releasing the beast. Holy fuck it was big, and getting bigger with every beat of the Dane's heart.
The thing was soon as big as it was going to get (I hoped!) and Mr. Reed just held my head as he slowly withdrew a few inches before pushing the whole thing down my eager gullet. He set a steady pace, fucking my throat gently enough that I could breathe fairly well. At least I think I was, since my head had started swimming the moment I'd felt that hot piece of canine flesh on my tongue. My tiny little nostrils were flaring, especially since Mr. Reed's knot booped it every time he pushed all the way in. I wasn't even sure if it was air I was desperate for, or the smell of that doggy-dick. All the while my hand kept juggling those hefty balls, wondering how long until I felt them tense up and feed me their big, gooey load.
I was sure I was about to feel a torrent of canine spunk spraying down my throat any moment now, when Mr. Reed suddenly pulled the whole thing out of my mouth, leaving me gasping for air. At least I think it was for air. My mouth was still hanging open after the workout my jaw muscles had gotten, and despite my experience I had teared up a little, making my eyeliner run into the white fur of my face.
Before I could get my bearings, I felt him pull me up like I weighed as much as a doll before he flipped me around and bent me over. I managed to grip a nearby shelf, and as I stared at stacked boxes of toner cartridges I felt his fingers hook into the waistband of my thong before he began to slide it down. My stiff little cock sprang free as the soaked fabric was pealed from it, and I wondered for a moment if I'd be forced to walk back home in such messy panties, or if the hulking canine behind me would take them with him as a trophy.
 Once they were around my ankles I felt his thumbs dig into the crack of my perky ass before he spread my firm cheeks as far as they would go. I was panting like a bitch in heat, my tail raised as high as it would go and quivering with anticipation. I could feel my little pucker winking, an inviting dot of pink in a soft, white sea. I was expecting one of those strong, thick fingers to come knocking at my door, and was quite surprised to instead feel a broad, thick canine tongue!
Such a gentleman! The truth was that although his attention was quite welcome (to the point I had to keep gripping the shelf to keep myself from falling over on my suddenly shaky legs) it wasn't strictly necessary. Whenever I had the Dane's classes, I always came to school spotlessly clean and well-lubed, just in case I got lucky, or so horny watching Mr. Reed that I was willing to accept a substitute dick.
Aaahh! Fuck, forget everything I just said, this is necessary! The sound I just made as the Dane's broad tongue slipped past my twitching ring was loud, but I'm pretty sure it was so high that only a dog could have heard it. The dog behind me certainly did, pulling my cheeks apart even more, making my boy-pussy gape a little as he shoved his muzzle between them. I wondered if this was how he always prepared his bitches - giving them a good working-over with his tongue until they were a panting mess, just begging for that thick red shaft. Or maybe he just likes the taste of strawberry lube...
Too soon I felt that wriggling appendage slip out of my stretched orifice, looking over my shoulder and giving Mr. Reed my most heartbreaking expression of desperate longing. Once I saw the Great Dane straighten, my face did a quick one-eighty when I saw that thick, dripping cock bobbing between those powerful legs.
It was a monster, but I was confident I could take it. Not because of the boys I had, or the men for that matter, but because of the sort of toys I practiced with. I had built up a pretty nice collection, financed by private, risqué cam shows I put on for people willing to pay for the privilege and not too worried about the whole 'underage' thing. My parents gave me an ample allowance, but that mostly went towards clothes and cosmetics. So I figured if I could take my stallion toy, I could also take what Mr. Reed had swinging (although it had only later occurred to me the silicone stallion didn't have hundreds of pounds of muscle behind it).
"Is this what you want?" the words brought me back to reality. Well, the words and the sensation of the tapered tip of the Dane's cock poking at my well-tongued pucker.
"Yes! Please..." I squeaked. I'd imagined this moment so many times, and even rehearsed the things I would say, but I felt a panic come over me at the thought that the dog of my dreams might change his mind at this point, so instead of sexy and seductive I just sounded horny and needy. Still hot though...
He wrapped his hands around my waist (fuck, almost all the way around!) and I relaxed, both knowing I was about to get what I wanted, and in order to be able to take what I wanted. The sound that I made as that red rod began to stretch me carried all my frustration and hornyness, a whorish cry of joy as my ass finally wrapped itself around Mr. Reed's shaft. He kept pushing it in at a slow but steady pace, forcing my body to adjust to that girthy spear, its advance aided by frequent spurts of hot canine pre deep into my needy hole. It hurt a little, but I made sure not to show it, worried it might scare him off.
God, is there no end to this thing!? I was sure that by now my flat tummy would be bulging from the massive package being pushed into my stretched butt. Inch by glorious inch went by until I finally felt the knot grind against my taught pucker, and I let out a shuddering breath I hadn't even realized I'd been holding.
Mr. Reed was merciful enough to give me a few moment's to get used to him, sliding one hand up and under my top to tweak my nipples. Every time he did my ass would clench around him a little and I would hear an approving growl from behind me. God, if he knew how to push my buttons this well, why did he wait so long to do it? As happy as it would have made me to just sit there impaled on his cock while his fingers explored my supple young body, the discomfort in my ass had faded and it was time to get on with the show, so I gave my butt a little wriggle to signal the hulking canine.
I whined as the cock slid out in one smooth motion, my pucker clinging to the slick shaft as if it was trying to hold on to it. But I didn't miss it for long, because a moment later the whole thing was shoved back inside with one powerful buck of those canine hips. My ears shot up and I squealed as the force of the thrust pushed me further onto my toes than the high-heels I was wearing. If the Dane hadn't had such a good grip on my girly waist, I'm sure I would have bounced off him when that knot smacked into my poor little butt. I might have complained about the rough treatment, but on its way in that steely doggy-dick had rubbed against my prostate in a way that no previous lover or toy ever had, so my brain wasn't really up to the task of forming words. Or thoughts...
Well, I'd done enough thinking for today, anyway. It was time to get to some serious feeling. Like the feeling of Mr. Reed's heartbeat pulsing through the canine cock now pistoning in and out of me. Or the feeling of his strong hands around my waist, pulling my ass back to meet every animalistic thrust. The sounds of his hips smacking into my ass, a noise that was getting wetter and lewder by the second. Aaahh! The f-feeling of his - ugh fuck! - his teeth on my ear!
That one proved too much for my poor brain to take, and seconds later I was mewling as my pucker clenched around the pistoning shaft, only serving to rub my prostate along its length as my cock erupted. Despite the modest size of my package, I always seem to cum like a fire-hose from a hands-free orgasm, and since my cocklet was bouncing wildly with every jack-hammer thrust that meant my bunny-goo was flying everywhere. Not that I cared at this point, although I was dimly aware of streaks of cum landing on my tank top (which I'll never wash again!) and a few even reaching my muzzle, and since it was hanging open as I moaned, my tongue.
When I came to what was left of my senses I blushed, realizing how quickly I'd creamed myself (and everything in front of me, really) when Mr. Reed had nibbled on my ear. In my defense, they were a sensitive area for all bunnies, and a major erogenous zone for me, something I'd never told a partner, preferring to let them work it out themselves. I figure if they aren't smart or curious enough to find out, they don't deserve the power to make me cum after only a few minutes of sex.
The Dane behind me still had my ear pinched between his teeth, pulling on it slightly to force my head up. This also forced me to arch my back and thrust my ass out, exposing even more of my rear to that pummeling cock. I was moaning for all I was worth as that red shaft slid in and out of my pucker, the pre now leaking from my overstuffed ass, trickling down and soaking into the soft white fuzz covering my little sack.
The doggy mating my rump had switched up his tempo while I was on could nine, and was now pumping at a lightning-fast pace, those strong legs flexing as they sent that throbbing red shaft sliding in and out of my tight little tunnel. The strong hands gripping my waist were probably the only thing holding me up at this point, apart from the canine cock buried inside me, that is.
The hunky Dane behind me hadn't cum yet, and having extensive experience with canines in general (due to a lack of experience with him in particular) I knew he wouldn't until he managed to tie me. Once that hard red bulb was in my ass I knew I'd be in for a minute at most of shallow, frantic humping as the thing grew even bigger, sealing me off before releasing a torrent of doggy-spunk into my quivering body.
Looking over my shoulder I caught his gaze and the look on his face told me what I needed to know. I was a panting mess and didn't trust my voice, so I just gave a little nod before bracing myself and doing my best to relax my pucker. Resistance was not only futile, it was painful! His trusts became harder, more urgent as I felt that knot spread my pucker a little more with every hard smack. I did my best to breathe, trying all the while not to think about how much bigger that thing will get once it's inside me.
The Dane breeding my ass had let go of my ear, which was a good thing since I could see how tightly his jaw was clenched as he tried to work the rest of his cock into me. His thrust became stronger and stronger until he shoved himself inside and instead of pulling out began to pull me back onto his massive rod. I winced, my pucker stretching out like never before as that big red bulb was being forced into me and I began to wonder if I had bit off more than I could, well... swallow. But once the widest point was in, Mr. Reed gave one final thrust, and we cried out in unison as his massive knot sank into my fluffy ass.
So far, so good, I thought as the canine cannon began to grow inside me while the male it belonged to began to wriggle it around in a sort of humping-grinding motion. I guess I was making a little too much noise because the next thing I knew Mr. Reed had slipped a couple of his fingers into my muzzle. Taking the hint, I closed my lips around them and began to suckle them like a baby while he prepared to plant one in me.
I knew the knot ballooning inside me should have hurt at this point, but the bigger it got the harder it pressed against my prostate, blurring the line between pain and pleasure. My ears picked up a long, growling groan from my canine lover a moment before I felt his cock twitch and the first of what I knew would be many ropes of puppy-batter squirt into my eager bunny body.
Fuuuuuck, this is my favorite thing about canines! Knowing I'm stuck like this, poor little bunny trapped on a big hard piece of dog-meat while my lover pumps a massive load into me, spurt by hot, gooey spurt. That warm, wet sensation spreading though my body as I'm well and truly bred like a bitch in heat. I even carry a little plug in my purse, just big enough to keep that load inside me for a while.
With every creamy pulse I imagined myself walking around with Mr. Reed's puppy-batter, my normally trim belly bulging a little as the warm, gooey mas sloshed around inside me. I always turn heads when I strut my tight little stuff, but when I've got a load in me, I usually manage to flare nostrils as well.
So lost was I in my little daydream that I didn't even notice Mr. Reed's fingers leave my mouth. I definitely did notice when the strong hand wrapped itself around my still sensitive shaft, letting out a little squeak as the canine impaling me got a good, firm grip. It was achingly hard, even though I'd cum a short while ago. It wouldn't have mattered if I'd had ten orgasms in a row, with that hard knot grinding and throbbing against my boy-button, there was no way my slim little cock would stay down.
I mewled as Mr. Reed began to pump my little cock while his monster was still squirting away, lodged firmly inside my shapely ass. I knew I wouldn't last long, and to be honest, I wasn't really trying to. All it took was a few minutes of vigorous stroking and I was moaning out as I felt my shaft spurt into the Dane's paw, a laughably tiny load compared to the one he was leaving inside me. And judging by his grunts, my ass must have felt amazing as it suddenly began to milk his cock for every drop it had.
I guess the big dog didn't appreciate the mess I made of his paw, since he brought his soggy hand back in front of my muzzle. Without any hesitation I began to moan as I licked and sucked my cream of his dripping fingers, earning a groan of approval from the satisfied canine. 
"Are you going to be a good girl from now on?" he asked in a low, deep voice.
"*pant* Is this what good girls get?" I asked coyly.
That didn't seem to be the answer he was looking for, considering the way he tugged on his knot before driving it back into me with a buck of his hips, making me squeal out in pain and pleasure.
"Yes! I'll be a good girl..." I cried out, knowing I would.