Yona's Extra Credit

by Nagiman

Rating: mature
Tags: Porn, Sex, Yona, Alternate Universe, Anthro, Original Character, My Little Pony: Friendship is Magic, Fetish
Length: 9015

Yona is desperate to get better grades. Things don't go as planned for her.

Yona the yak has been failing hard in classes and now it's the end of the year. Desperate to up her grade she approaches her worst two subjects. Sexual Education and Biology. Luckily she finds both those teachers in the same room having a small meeting. Her offer doesn't go quite as she plans as the two take full advantage of the naive yak.

Contains - M/M/F, Scat, Watersports, Farting, Squirting, Smegma, Anal, Vaginal, Oral, Double Penetration, Mindbreaking, Semi-blackmail, Dirty Talk, College-Aged Yona, Older Men

Published 2022-03-08 05:50:00 UTC
Last updated 2022-03-08 05:50:00 UTC

S is for...

The final bell for the day rang at the school of friendship, students and teachers alike packed up for the day, emptying the classrooms and hallways. However not all teachers were leaving, some stayed behind to finish grading work and tests, some went to relax in the staff room, and a few were having meetings. Two teachers sat in one of the classrooms conversing about the day.

Professor Galbrid the griffin and Professor Hightide the hippogriff sat discussing how they were finishing up the grades for the semester before returning home for a well-deserved vacation that year until their classes would be taught again. The two males were nearing the old age of retirement but still quite spry when it came to teaching students at a higher level.

As they spoke away, a knock at the door interrupted them. It slide open and a head popped in of the young yak girl, Yona. She waved to the two of them before saying, "Hello Professors. Can Yona speak with you for a bit?"

Both looked at each other for a few seconds before Galbrid responded, "Of course Yona, you are more than welcome to speak." He waved her into the room over to the desk they were sitting at.

Yona slipped into the room, shutting the door behind her. She was dressed in her white button-up top that barely held her big breasts underneath, straining the buttons to their limit, her blue plaid skirt for the school uniform swayed in the movement of her big rump, with knee-high socks and black platform heels. She approached the desk, her hands behind her back as she innocently stood there for a few seconds building her courage to speak. "Yona wanted to talk about her grades. She knows that she hasn't been the greatest but was wondering if you could allow for some extra credit in her classes." She gave the pair a sweet smile as she turned her hips back and forth.

"I'm sorry dear, but my grades are finished for the year. There is no more room for more grading or improvement in my sexual education class." Hightide shook his head in disappointment. "I wish I could help you out but those are the rules. Once I submit them today I am done."

Galbrid tapped his finger on his desk with the same disappointed look as his fellow teacher. "Sadly I have to say the same about biology too. We were just discussing what we were going to do on our time off after we dropped off our grades to Headmare Starlight. I'm very sorry Yona, is there anything else we can help with?"

The yak's smile faded into a small frown, her green-painted lips falling from her usual happy demeanor. Her arms dropped to her side as she felt the weight of her disappointment weight down. "Yona understands. Yona was hoping that she could get just a bit more to be better looking for when she went home." Her mind struggled to figure out what she could do until she made it halfway to the door. She turned around and walked back to the professors, "One thing does come to mind. Could Yona make it up in another way?" She crossed her arms under her big breasts, giving them a puff to signal some attraction.

"Not that I can think of dear. We're pretty much solid on the grades," Galbrid retorted.

"Yona means she'd do anything to improve grades. Even have sex with professors to get them if need be." She wiggled her boobs some more as the shirt swayed with the movement of the big beasts she sported.

Both teachers dropped their jaws in shocked silence. Their eyes were as wide as saucers as looking between each other and the yak. Sitting in silence the whole group stood still in time, Galbrid thinking his options through, while Hightide felt his body tingling in anticipation at the opportunity. Yona stood there in her sultry pose trying to tempt both teachers with her body in a single go.

Hightide managed to stutter out, "I... I... well... I don't see that as a problem. What about you Galbrid?"

The griffin looked even more shocked at his partner sitting in the room. His mind now shifted a bit at seeing how this big busty and thick girl would look between his legs. His dick quivered at the thought of having her pleasure his pecker since it had been a while since the last time he had sex. He even imagined some things he had wanted to do with other females but was shot down, now he held some power in his hands. He cleared his throat before saying, "I'm sure we can do that, however, there will be some conditions."

Yona bounced in place clapping her hands, causing her skirt to lift a bit, and breasts to bounce. "Yes, Yona can agree to conditions. Yona is excited to get better grades."

"Well hold your horses there missy. Better not agree until you hear the conditions first. The first condition is that nothing leaves this room and stays between the three of us. Second is we can film this to make sure we get a good share compared to raising your grades, and lastly, you'll do whatever we say without complaint or the deal is void and you get no grade increase." Galbrid held out his hand to seal the agreement. "So do we have a deal?" He gave the girl a sly smile.

Hightide looked at his fellow teacher and saw the cogs turning in his head. He knew what he was up to and wanted to get in on that too. From past discussions, they had outside of work it would be one hell of a time. He turned to Yona as well, holding out his hand, putting on the same smile. "Well, what do you say Yona, are you on board with those terms?"

The yak stood there pondering the conditions they laid out before asking, "So video stay with just you two? It doesn't go out for others to see, yes?"

"Of course, why would we do that to such a beautiful girl as yourself." Hightide lied through his teeth knowing he could make some serious cash with this to the right buyer.

Yona gave one last look at both teachers before shaking both their hands in agreement. "Yona agrees. She'll do whatever she needs to have better grades."

Galbrid got up from his desk and pulled out his phone, getting it ready to film. "That's good, just give me a few seconds here and I'll be all ready to start."

Hightide did the same, pulling out his phone and getting it set up for filming the yak. "I'm ready on my end. Just say the word Galbrid and we'll get started."

With a few more button presses, the griffin had his phone all set to film. "I'm ready, so go on Yona, why don't you strip down to your underwear for us to start with. Make sure you go slow and show off all your sides."

Yona nodded at the two teachers. "Of course, Yona take her time to show you how beautiful she is." She started by turning herself around, pointing her rear to the cameras first, and swaying it side to side, while her skirt flipped up peeks of her green panties underneath. Turning back around she started to undo her buttons one by one, letting each one pop between her fingers as she went down. After reaching the fourth button, her big green bra and the giant ribbon in the middle of it could be seen between the small gap forming in her shirt.

Both teachers licked their lips as they held their cameras up to catch the action. Galbrid began teasing his dick with small strokes of his free hand, while Hightide had slipped his hand fully down his pants and was fondling his wrinkly balls.

Finishing off the buttons of her shirt, she pulled down the white fabric and let it fall to the floor, freeing her bra from the coverage. It was a big green bra, with darker lace over half the cups and a dark green ribbon in the middle of the breasts that hung down almost to her chubby belly. Yona took hold of her tits from below and played with them for the camera before giving them a shake to show how much jiggling they could do. After a few minutes of showing off how great her breasts were, she moved to her skirt, slipping her fingers down the sides and swaying side to side to slowly lower the small thing. She turned around as she swayed, showing off her ass again with the big green panties covering a majority of it as the skirt slipped down until she let go and it fell to the floor on its own. She turned back around her hands on her hips as she thrust her groin forward and back in small circles. The frilly skirting on her panties, with two big ribbons just slightly off to the sides, on the front of her panties flipped with her movements. Her puffy cameltoe could be seen through the panties as she moved.

"Oh my, such a beauty you are my dear. Such lovely underwear as well." Glabrid felt his dick getting hard under his slacks and wanted to get them off sooner rather than later. "Such a good performance as well, I think that itself can raise your grade from a D to a C for my class."

Hightide pulled his hand out from his pants, his dick tenting against the fabric. "I know, such good work is put into it. I think that is the same with me as well. The way you played with your breasts and the swaying of your thick hips was just perfect."

Yona took a small bow at the praise she got from the teachers. "Thank you, Yona is happy you liked it. Now, what does Yona need to do?"

Hightide got up from his chair and stood there waiting for Galbrid to join him. When the griffin stood up as well, both approached the yak so they were closer. "Well, next you can take off our pants for us. Since our hands are tied up holding the cameras we'll need you to do it for us. Don't worry about going slow get them down as soon as possible."

"Exactly, we can't set these down and miss out on the actions you take. After all, it wouldn't be fair to give a good grade without catching why we should, on camera." Galbrid smirked as he felt his bulge starting to form as well.

Yona said, "Of course, Yona will take off teachers' pants to make sure they can film." She reached towards Hightide's groin first, undoing the button and zipper before reaching his hips and grappling the fabric. She managed to pull down both his pants and boxers at once, releasing his knotted horsecock in front of the girl. A pungent smell and grimy yellow build-up met with the yak, causing her to gag just a bit. "Phew, Professor Hightide, you need to wash better. Yona only smelled something this bad back home when the animals were being cleaned." She waved her hand in front of her face to try and remove the stench of sweat and dick cheese.

"Don't worry about it too much. It's not as strong as you may think once it is aired out. Being cramped up all day will do that." He chuckled to himself as he watched the girl shake her head a bit before moving over to Galbrid.

Doing the same for the other teacher, Yona pulled down his, letting out a spined pointed cock with a small knot and much more growth over his dick. It didn't smell as bad as Hightide's but it certainly caught her eye much more. She pointed to the smegma on the griffin's dick and said, "Yona thinks she remembers the lesson on this. Sme.. smeg... uh... what did friends giggle about it again." She sat there and wondered for a bit before saying, "Dick cheese. That is what friends said about it. They said it was a nasty thing on boys' penises."

The hippogriff smiled at her and nodded. "Yes, smegma, or as your friends put it, dick cheese, is built upon male genitals, but it's not as bad as they make it out to be."

"Certainly so. Now go on and be a good girl and give our dicks a good sucking and cleaning with those fancy glittery lips of yours." Galbrid wagged his dick side to side in front of the yak's face.

Yona adjusted herself on her knees, keeping her head level with the two dirty dicks. The smell was still off-putting but the sight reminded her of yak cheese back home. She reached out, taking a dick in each hand, the gooey texture of the smegma wrapping around her fingers as she took hold of the old cocks. Leaning towards Hightide first, the smell increased greatly, with the amount of sweat he had pouring off him. "Yona is still a bit nervous as it's her first time. Are you sure about this?" She looked up at the hippogriff with pleading eyes.

Hightide looked down at her through his phone camera, the sweet innocent eyes just begging for defilement to him. "That's fine sweetie, go ahead and take your time, but I'm positive about this if you want to increase your grades more. You've already done so much just to get it from a D to C, now let's get it from a C to a B."

"Of course, you could back down and we void that upgrade already and call things off if that's what you want." Galbrid shrugged his shoulders.

"No, no, Yona will do it, just nervous is all." She smiled back at the camera before opening her mouth and giving Hightide's dick a lick, taking in the salty putrid taste of the smegma that coated his shaft. It had a partially familiar taste, almost like it was cheese made in the homeland but slightly off from its texture. She moved closer as she got her tongue further down along the dirty mess, taking in the nasty taste of old socks and rubbish, but still getting used to it as she switched over and started to give Galbrid's dick some tickling as well.

Galbrid let out a moan as he felt the young tongue lapping away at his build-up, her hands gently rocking back and forth on their dicks. "She certainly knows how to use her tongue and hands for a first-timer. I certainly think she's going to be great at actual sucking."

Yona kept up her work, switching back to Hightide but this time opening her mouth and sticking the dick inside. Her lips nibbled on the fleshy stick, staining green lipstick into the mess of yellow goo onto the pink skin below it. Her mouth filled with the taste of smegma as she moved back and forth. She gave a big inhale as she pulled herself off his dick, taking a good chunk of dick cheese with it.

"Holy shit, that was crazy good. Go on and open your mouth, let's take a look at all that dick cheese you got in there." Hightide zoomed in with his camera, focusing hard on Yona's maw. She opened wide showing her tongue nearly coated fully with the yellow goo, and a big wad of smegma just sitting at the tip of her tongue rolling around as she wiggled her muscle. "Fuck ya, that's super hot, go on and eat that up."

Biting down on the wad, the paste mashed into her teeth over and over, giving the effect of glue until she took a moment to swallow. The mess swiftly went back into her throat and down to her stomach. She felt her stomach try and reject the nasty treat but she kept her constitution to not upset the teachers. "Yona thinks it tastes funny still but will keep going until both are clean." She started again back on Galbrid, taking his cock just as she did with Hightide, her lips staining the spines in green as she stuck on them a bit more trying to get the smegma clear on them.

"Damn, you are right Hightide, she certainly knows how to use those lips of hers. She's painting me greener than a frog with that lipstick of hers. Must be from the cheap whore section." He laughed as he watched the yak swallow down more dick cheese and shivered from it.

She went to switch back to Hightide again before he stopped her with his hand. "Alright dear, I know it isn't fully clean, but you've done enough for now. Why don't you stand up and take a break from crouching down on your knees." He took a step back with Galbrid to let the yak get back to her feet.

Yona got back to her feet, her stomach feeling a bit uneasy as she felt the bits of dick cheese remaining on her lips slip into her mouth. The after-taste still lingered on her breath and taste buds, while the goo stuck to the small cracks in her gums. "I'm sorry I didn't get more done. Yona promises to do better."

Hightide shook his head to the young yak, "No, that isn't a problem. I stopped you before you did because I think we can move on to something a bit more fun. Go ahead and climb up on the desk and lay down with your head hanging over the edge."

Walking over to the desk, Yona was a bit confused but complied by getting on the desk, her head hanging over the edge, with her braided loops swaying in the air as she lay there. Galbrid marched over to her, taking hold of his dick and aiming it towards her mouth. "Now open wide and hold still, don't need to make a big mess now." He waited for the yak to open her mouth and hold still before letting loose a spray of urine that struck her chin and face before straightening out into her open maw. The salty fluid filled into the roof of her mouth as she lay there wanting to spit it out but refused to make the old teachers mad.

The hippogriff clapped his hands together slowly for a few goes before turning to his fellow teacher. "Good idea Galbrid, I didn't think about cleansing her pallet for the next bit. Drink up Yona, that'll help clear the taste from your mouth."

The yak did as told slurping up the piss filling her mouth and getting hit in the face when she closed her mouth to drink what flooded inside. Her breasts slipped down to the side of her chest from their size and weight with the help of gravity, her hand was finding its way down under her panties to touch her now wanting pussy. The dirty work she was doing was beginning to turn her on.

As the stream tapered off into just a few drops, the griffin shook his dick over the open mouth to get the last few drops fully drained. "That was great. Always wanted to piss into a living toilet, and thought it would help as well. Go on and give it a try for yourself, Hightide." He gestured towards Yona laying on the table.

"I'm good for now. I had something else in mind. Yona, I heard that you like chocolate, but always found pony chocolate to be a bit weak in taste. I think I have just what you need though. Rich, thick, and chunky hippogriff chocolate. Now make sure to eat up as much as you can as fast as you can though." He walked over to the girl and lowered his shit-covered ass cheeks over her face. The rancid smell of unwashed and leftover crap filled the yak's nostrils as he lowered himself down on her.

Yona tried to turn her head away before the two cheeks trapped it inside. Her efforts were for naught as her voice was drowned out from the flesh covering her face. The feeling of his ball sack on top of her head as his butt let out wet and wild farts. The smell of the gas overwhelmed her to the point she tried to push him off with one hand, but her other had a mind of its own and kept pleasuring away at her pussy.

Hightide pushed as best as he could, letting out trumpet after trumpet of foul air out of his posterior before the solid mass in his ass gave way and started to move to the exit. The slithering brown turd poked its head out and greeted the yak who was coughing from her stink spraying. It lowered down slowly with a slimy coating on the outside, reaching Yona's mouth she opened, letting the crap break off and into her maw. More of the shit continued to slip out of the wide-open hole with Yona rushing to keep up with it.

Gnashing away at the dirty butt fudge, Yona found herself wanting to throw up, but also enjoying the attention she was getting. This was something most foul but it was her stupid suggestion that had gotten her in this mess and she did need the grade approval or her father would never approve of her coming back next year. She kept thinking of the reward at the end of the title as she opened wide for the next log to drop into her mouth. Her teeth and gums stained brown from the first piece of shit, and now the next one making it a bit worse, while her lips gained small little bits where liquid crap slipped out in her saliva.

The hippogriff let out a few smaller nuggets before blowing another blast from his ass and spraying her face with bits of fecal matter that had clung to his taint. He lifted himself off the yak to get some personal footage of her eating his shit while Galbrid had gotten a close-up view of it with his phone. "That's it you sweet little slut, chew my shit like the sweet fudge it is."

Yona gave a few more bites of the turds before opening her mouth to show off the mess in there before she swallowed down the mass and gave the camera another view of the now-empty maw. Her stomach turned more as the shit made its way down, the flavor and after taste, she couldn't place but it certainly wasn't chocolate that she'd eat all the time. "Yona doesn't feel too good, but she wants to get better grades." She moaned as she rubbed her belly.

"That's okay, you don't have to eat more of it for now. Climb down from there and lay across the shorter way." Galbrid gestured for her to get down off the furniture. "That's it now, nice and careful." He watched as the yak got down off the desk and leaned across it, her breasts squishing against the solid object as her ass stuck out. Galbrid walked over to the yak and caressed her shoulder before moving down to her ass, his hands rubbing over her cheeks and the soft cotton fabric of her panties before he slipped his hand down into her butt crack. "Ya, nice and big, that's the way I've liked them." He licked his lips before lowering her underwear enough to see the actual big booty she sported.

"So what are we doing next? Yona is wondering when this will be over." She wiggled her legs a bit as she felt the hand rub between the cheeks a bit more and prod at her asshole.

Galbrid spread open her cheeks to get a nice view of a browned taint waiting behind the big booty of the yak. He kissed her butt before responding to her. "Oh, we're going to be playing anal cleaning. Where I stick my dick up your butt and fuck it until the rest of this smegma is cleared off. Then you can clean the mess off with your mouth again. That should be enough to get you up to that B mark, though we'd have to do a bit more if you want an A or even A plus. Now be a good girl and jiggle your butt for us before I start putting my pecker in it."

Hightide got his camera filming the side view as Galbrid got the rear of the yak twerking her butt for them. The big mass in a constant motion from the fat in it jiggling like a bowl full of jello. Her hips swayed side to side and in circular motions as she put on the little show for the two old men. Galbrid smacked her ass now and then as she danced away to the moaning delight of the griffin.

"Okay, you can stop moving now. I think I'm ready to get into your tight little shit hole." He grinned with glee as he approached Yona from behind. He spread one of her thick ass cheeks with his hand while holding his phone, the other handling the base of his shaft, to line up with her taint and to not get his hand covered with the leftover smegma still on it. With a bit of aiming, he finally got his dick to penetrate her tight ass. The feeling was overwhelming as her tunnel clenched down right away on his dick, sucking away at it and scraping the smegma off as if it were nothing. The gooey dick cheese made a makeshift lubricant as he sunk his dick deeper down into her bowels.

"Your penis feels weird up Yona's butt, not a bad kind but a strange kind. It makes Yona feel better at least." She lay against the desk as the griffin humped away with fervor. As she lay there her butt let out a large fart as the griffin pounded away which got her a loud moan from the teacher. Knowing that he seemed to like it she let out a few more, again receiving moans from him as she did it. She smiled in the knowledge that he was enjoying fucking her noisy smelly ass.

The hippogriff grew tired of just watching on the sideline and approached Yona from the other side of the desk. He held his now aching dick in front of her. "Don't leave me waiting you little slut, go on and suck my dick again while Galbrid fucks that nice ass." His wish was granted as Yona opened wide and bobbed her head with the pounding she was receiving from the griffin. As she sucked away the smegma broke off into her maw, leaving more green stains on his cock, even reaching his knot near the base.

Galbrid started to spank the yak as he fucked her ass, the sensations starting to drive him wild. "Holy shit, she's got some fat ones waiting in here too. I can feel them with my tip. You certainly are a catch." He reached for her back and started to unhook the big bra strap she wore to support her breasts. With a few swift movements, he managed to do the job, letting the clasps fall to the side. The griffin started to feel his bowels now wanting to empty, and to go right now would be such a waste of an opportunity of using a living toilet. "Hightide, let's swap, you can have a turn with this amazing shit hole."

Hightide nodded to his partner and pulled his half-cleaned dick out of Yona's mouth. Galbrid did the same pulling his dick from Yona's ass, coming out covered with brownish goo coating across his cock. They swapped places letting the yak catch her breath for a bit before Hightide got his bigger cock inside that small pucker. He grunted as he worked his way in, stretching her butt wider than what Galbrid had done. One hand of his gripping her ass as the other tried to get the best angle of penetration on film. "Fuck you were right Galbrid, she's fucking tight as hell. I might blow my load early from this."

"Ah, professor Hightide's dick is much bigger. Yona feels her butt stretching wide." Yona said before biting her lip for a bit as she felt the hippogriff push his knot inside. It was certainly deep, and her ass stung a bit from the increased girth that had entered into her pucker. However, she couldn't stop but felt even needier of the cocks and attention.

The griffin grinned at the sight of the girl in throes of bliss and pain. He set his phone up on the desk to get a nice side view shot of what he was about to do. He turned himself around, planting his ass inches away from Yona's face. Letting out an airy fart right into her nose and mouth that smelled as if it had been garbage sitting in the summer heat for days. He let out a few more with his body feeling more relief as he did. "That feels so good getting those out. Now get ready, here comes griffin chocolate just for you." He strained his butt muscles a bit before another blast of warm smelly air hit the yak again, then his white stained taint twitched and opened wide, letting a white turd mixed with flecks of black and brown slither out and down towards the yak's mouth.

Yona opened her mouth to let the descending log in with ease. The taste was that of seed, salt, and a bit of garbage. She snapped it in half with her teeth and started to chew away at the offensive object. Her teeth, gums, and tongue getting coated in the weird colored bird shit, but the taste certainly blew away Hightide's butt fudge that he had earlier. As she chewed away at the first bit, more came out of the professor's ass, while the other pounded away at hers, forcing her face into the logs coming out. Bits of crap landed in her hair, on her nose, and others onto the desk. When she finished the first load she opened up and started putting more in her mouth to appease her suitors.

Hightide slammed his dick in the yak's ass a few more times before his knot started to enlarge, making it harder for him to thrust in as fast and hard as he wanted. His hand still holding one of her cheeks to the side, he managed to get a shot of his knot pulling hard on Yona's anus as he tried to pull it out. His breathing became shallow as did his thrusting before the rush of an orgasm overwhelmed him. His tip flared up and he came, filling the tight tunnel with his sticky seed. "Fuck, take it all you whore, take my load." He managed to moan out as he drained his nuts into the yak.

The warm gooey feeling in Yona's ass made her moan as well with shit in her mouth dropping out onto the desk. She swallowed what was left in her mouth before continuing her enjoyment of the teacher's orgasm in her anal cavity.

Galbrid had finished with his shitting at this point and turned himself around to see the show. He picked up his camera to film the yak with shit on her face and in her mouth moaning at the anal attack of sperm she was getting. "Hell ya, look at you, you little slut. Enjoying all this attention aren't you." He grinned as he picked up the remaining shit and dropped it into her mouth. "Now go on and finish sucking me off with that as well. I'll make sure you get a good creamy filling on this end." He planted his cock just on the shit he put in her mouth and waited for her to start working.

Yona wrapped her mouth around the dick and shit. Sucking away at the small bits of smegma left on the cock at the time. The log spread around the male meat as she sucked away, bobbing her head up and down his length. The shit spreading along it gave the whole shaft that strange taste she was enjoying. Her lips tickled his spines as she reached the tip before taking the dick deep to the point of the edge of her throat. At this point, her lipstick had been coated in the white shit and no longer was spreading the cheap green stains. As she worked at the griffin's cock, she felt the hippogriff finish cumming in her asshole. The knot and flare shrinking down in size, relieving her of some of the stretching.

Hightide gave the yak one more spanking before pulling out his dick, coated with his cum and some brown slime from the yak's anus. He got his camera close to view the leakage from the yak's ass down to her pussy. He smiled as he watched his work in progress slowly trail downwards. "Oh fuck that was great. I just need a little bit to get ready. For now though..." he said as he grabbed Yona's panties and slid them back up over her ass. "I'll just let Galbrid finish first before we continue."

The griffin bit his lip from the pleasure, his body shaking before he could take the yak's mouth no longer. He let out a screech and his load. Filling Yona's mouth with his cum, mixed with a bit of piss. The sweet and salty, acidic mixture took over the taste of the shit that she had finally turned into liquid from the motions. He gripped the desk to keep his balance as he shot rope after rope of his seed into the girl's mouth. His breathing reached short peaks as he let everything out.

When Galbrid finished cumming into Yona's mouth, she opened wide to show the camera what was produced and how messed her mouth had become from all the shit. The inside looked like a giant can of paint had exploded and mixed with some dirt and sunshine. The pool of brown, white, and yellow swirled around over her tongue before she closed and swallowed the mixture in a single gulp. Her stomach-turning was less than it had before.

Galbrid patted the yak on the head and said, "Good slutty toilet. You've done such good work. You've certainly earned that B now."

Hightide rolled his eyes at the griffin as he approached near his partner. "Yes, you've done well, but we're not done yet. Come down off the desk and let us see those tits you've got, and while you're at it, why not tent out your panties with the shit you've got built up, just for us."

Yona lifted herself off the desk, letting her bra straps roll down her arms and off onto the floor. Her massive double D-sized boobs sagging with gravity, with her inverted nipples hidden away in the flesh. "Yona doesn't normally take off her bra except when showering. It feels strange having them hang down." She poked at her breasts with her finger.

"Well, they certainly should be out a bit more on display. Their shape and size are too good to hide behind that prison." Galbrid picked up and held her bra in one hand, giving a good view of it with his camera checking out the size of the cups and straps.

Nodding her head, Yona looked to Hightide. "Yona shall now poop in her panties as you want." She turned around and took a squatting position, her ass on display behind the veil of green fabric again. She let out a few more blasts of warm air before her pushing was rewarded. A big thick log squirmed its way out and pushed against the fabric, forming a small tent shape before it broke from her ass and pooled in the bottom.

Hightide stroked his cock a bit as he watched the yak drop another turd into her cotton panties. The tent became bigger as the weight of the shit pulled down against them. Licking his lips as he watched her make a small show of it as she wiggled her butt side to side as more crap wriggled out of her pucker and plopped into the pile. The smell of yak manure started to fill the room as she took her time getting it all out.

Galbrid was in the same situation, his dick getting some attention from himself as he watched the yak letting it all go. Then the sound of liquid hitting the floor caught his attention. She was pissing through her panties from the strain of pushing her bowels out. It was turning the griffin on seeing her stain her panties with both the brown from her shit and the liquid flowing out of her pussy. "Seems we got a small bonus eh, Hightide."

Yona blushed hard as she let out another log into her panties. "Yona sorry, she didn't mean to pee herself." The liquid pooled beneath, surrounding her feet as she let out another airy fart and smaller dropping of nuggets.

"Don't worry about that. I figured it might happen if you pushed hard enough. Plus, that dump looks like it was pretty big. Just the sagging of your panties shows that." Hightide pointed towards the now large lump hanging behind the yak of all her shit. "Since you've finished letting it out, come on over and drop those to the ground so we can see how much you let go in there."

The yak waddled over slowly, her panties sagging and swinging with the weight of the manure pile tapping against the back of her legs as she moved. Her body tingled in both some shame but also in pleasure from the risky adventure this had turned into. Once she made it over to the teachers, she slipped her thumbs under the waistband of her underwear and carefully pulled them down to the ground, stepping out of the leg holes and leaving the brown filled green panties wide open for them to preview.

Galbrid stroked his now re-erecting cock at the sight and smell of the mess she had made and presented to them. "Certainly that couldn't have all been in you. Quite a sight to see though from this close-up." He gave her a creepy smile as he looked from the pile to her.

"I'd say it's one of the biggest I've seen myself," Hightide nodded and walked around the yak and her mess like a predator circling its prey. His finger ran along her shoulder to shoulder before he stopped on the other side. "Even now I'm just getting hard thinking of this next thing to get you your A grade. Get down on your knees and spread your shit all over our dicks. Lay it on real thick." He licked his lips as he presented his now hardened dick to her.

The griffin joined Hightide presenting his dick as well to the yak. Yona looked at both of them before kneeling before her pile of shit. Her hand reached in and grabbed a good handful of crap, squishing between her fingers as the dark brown shit broke into pieces. She reached for Hightide's dick first, slapping a hefty chunk of warm manure onto the pink flesh soaked in leftover cum. Moving her hand along his length she spread the shit like peanut butter onto bread, smearing thick globs across his dick.

Hightide shivered in delight as the warmth from her crap was certainly pleasurable but was more excited about shoving it up the yak's cunt. "That's it, coat my cock with your feces like a good slut."

Yona smiled up at the pair. "Yes, Yona is a good slut. She listens to teachers so she can get good grades." She grabbed another handful of her shit and started coating Galbrid's cock with it. The spines tickled against her fingers as she worked her turds around the little prongs, getting the mass mushed on. At this point, she had only gotten half of her pile coated onto them both.

"Geez, this is nice. I can't believe what we've been missing out on for so long." He moaned as he felt the fingers weave between the spines before she grabbed some more crap and worked it down to his knot, painting the pink balloon to dark brown.

The hippogriff nodded in agreement with his counterpart. "I'm surprised none of the other students have come wanting better grades with such an offer." He chuckled as the yak dropped another handful of shit along his shaft.

Yona had worked enough of her shit onto both cocks to have them thickly coated in the dark brown manure and still had another handful leftover. "Yona is finished with rubbing your dicks with her poop. She still has a little left. What should she do with it?"

Galbrid's eyes narrowed as he looked at the remaining crap and got an idea. He picked up her bra again, setting it on the ground. "Go on and fill your bra cups with it and put it back on. You deserve to feel it just as much on your chest."

The yak complied with a nod and moved the shit from her panties into each cup of her big bra. When it was fully removed from her underwear into her bra she picked it up by the cups and squished it against her breasts. The shit smeared and squished under her hands' weight as she made sure to get it on her tits before she reached around and did the main strap to keep it in place. The warm feeling on her boobs made her quiver with delight as her pussy let out dribbles of fluid in excitement for what she was doing. She felt it was right doing this now, every bit of shit and smegma was well worth going through so she could increase her grade and she was on the doorstep of reaching an A.

Hightide climbed onto the desk and lay down, his shit-covered cock standing at attention. "Now then, we should be good to finish this. Come on up Yona and get this dick deep into your pussy." He patted his legs for the yak to climb up on top of him.

Galbrid followed behind her, helping Yona to climb on the desk and over Hightide. "That's it, shove that right up your cunt."

Yona's pussy ached in anticipation of shoving the dirty dick deep into it. Taking her time to adjust herself, she took hold of the knot with her hand, squishing the shit on it more as she aimed the tip to her virgin folds. As the tip prodded her lips, she bit down on her lip, the warm sensation teasing her clit. With a bit of wiggling, her flower opened wide letting the cock sink in with the stinky shit spreading on the outside and smearing the inside as it went deep into her. Yona moaned as she felt the cock stretch her insides, feeling the length get deeper until it pressed against her womb. When she had bottomed out she was grabbed by her breasts from behind pulling her back against Hightide's chest.

The griffin figured out quickly what his partner was doing and he took his chance to move. He lined up his cock with the already penetrated pussy and pushed his way in as well. The massive amount of shit on both of their dicks acted as a great lubricant for them to both fit in with ease as they stretched out Yona's pussy. Galbrid held onto one of her legs to keep himself steady as his camera was the only one going to get a good shot of the whole thing. "Holy fuck she's a tight one. I don't think I'll last long doing this for the second round."

"That's fine, let's just get this whore filled with the good stuff." Hightide replied as he started to pump his cock as much as he could with the confined space. His hands fondled the big yak tits, smearing the crap around them even more as he moved them around like big pillows. "These tits of yours are quite soft. I'm sure next time we can make sure to use them a bit more." He kissed Yona on the cheeks as she screamed in delight from the pussy pounding she was getting.

"Yes, fuck Yona's cunny, fill her with delicious man milk and her shit. Please don't stop fucking Yona." She let out in a loud burst as she felt the two teachers pelting her pussy harder with their thrusts into her. The pain she felt was nothing compared to the pure pleasure she waited for. The feeling of the hands, on her breasts pushing around the shit more onto them, the dicks deep in her love tunnel pounding away, and the remains of shit still on her lips was driving the young yak into a sexual frenzy.

Galbrid slammed away as best as he could, his spines on his dick pushing and pulling as he moved in and out of the tight space. His balls slapped away at Hightide's, his hand trying to stay as stable as he could while he filmed both the penetration and the yak having a fit of sexual induced euphoria. "Fuck fuck fuck, this is too good. Holy shit, I can't hold on much more Hightide." He gritted his teeth trying to stop his orgasm as the wet tunnel started to squeeze on both the cocks, trying to milk them like a pump.

Hightide gritted his teeth as well, his hands grasping for dear life onto the breasts he was fondling. "Fuck, ya I can't... fuck it, let's fill this bitch." Those were the last words he got out before his flare and knot expanded, letting loose a torrent of cum into Yona's womb. The feeling of sweet release in the tight virgin pussy was amazing, but the feeling of the warm cum from his friend spraying against his dick made it just as good as it soothed his aching needs.

Yona let out a scream of pleasure as she squirted hard against the griffin, coating his groin in her juices. "Yes, fill Yona's cunny, fill it as full as you can." Her chest heaved up and down as her breathing became heavy from the excitement and adrenaline.

The griffin filmed the whole orgasm, from the gaping mouths to the squirting yak, and creamy cum that dripped out of her vagina. Everything was caught as Galbrid struggled to stand up as his dick melted in the orgasm.

The trio of sexual deviants lived in that moment for quite a bit before all the cum had finished being shot up into Yona, and she finished with her torrential squirt of feminine juices onto the griffin. The time passed as all three were tired out from their triple orgasmic release. Both males' dicks started to deflate from their erect state and slipped out from the yak's tight hole, a wellspring of cum following as they slipped out of her.

Glabrid got a nice close shot of the gaping, quivering, leaking pussy as the yak lay there in a semi-conscious state from her orgasm. "Holy fuck, we did a number on her down here. So much cum dripping out of her, and the way she squirted has me soaked." He stuck his finger in the light brown mixture and ran a trail of it up her belly.

"That's nice and all, but look at the time. We need to hurry up so we can turn in those grades to the Headmare." He pointed to the clock on the wall. "Alright Yona, up and off, just need you to lick our cocks clean so we can report your A grade to the Headmare." He patted her thigh to encourage her to move off him.

Yona slid off the hippogriff and shakily got to the floor once again. Her body felt heavy, tired, and full, yet she was able to steady herself as the teachers presented their dicks to her. She started with Galbrid's, sucking off the shit and cum off his spined cock, slurping to the base in a single go. Her tongue lashed around to get the taste of her ass and his dick all over her mouth. She moaned as she did so, sending small vibrations through the griffin one last time before popping off with a wet pop and a kiss to his shaft.

"Thank you Yona," said Galbrid as he patted her on the head. "You've been a great little shit slut for us and very deserving of that A grade. If you let me keep your panties, I'll give you the A+ that you want."

"Yes, take Yona's undies, you can have them all you want," she said in excited glee. She turned to Hightide next and started to lick clean his cock. It had a much thicker coating of shit still on it along with a good helping of cum. The sticky mixture clung to her teeth and gums as she sucked away at his much bigger dick.

Hightide watched and filmed the last bit as she drained the mess from off his dick and the least bit of cum still stuck in his urethra. When she pulled off his dick had a thin layer of spit on it that made the flesh shine like polish on a floor. "Certainly you deserve the best of grades. Now hold still while I shower you with the best celebration ever." He held his now flaccid dick up and let loose his bladder, showering the yak with his piss. Her face was first in the stream as it rained down on her, slipping down to her breasts and then the floor as it dripped off her.

Yona opened her mouth at one point to drink down some of the golden shower. The taste of urine tingled her taste buds one last time before she swallowed what she had taken in and let the rest cover her face. As the stream died out she looked up at Hightide. "Will Professor give Yona an A+ as well?"

"Of course, and I've got something else as well for you." He went to the desk and opened the drawer, pulling out his wallet. He took out a good handful of bits and passed them to the yak. "Go ahead and buy some more lingerie. Something sexy for yourself."

Taking the money in hand, Yona clapped with joy. "Yes, Yona buy even better underwear for teachers’ pleasure. That way next year she can have even more fun times." She smiled with the biggest grin on her face until an idea had hit her. "Umm... Yona would like to ask for one more favor. Could you tell other male teachers for next year that she would like to get even better grades as well? Yona is more than willing to fuck more teachers for better grades."

The pair looked at each other, big grins growing once again. "Of course Yona, we wouldn't mind telling some others to help you out. Especially since you've been so good so far. I'm sure next year will start with a good bang." The griffin elbowed his friend.

"Most certainly. I'll make sure to save up much more dick cheese for you as well. Nothing wrong with having more for such a beautiful toilet like you around. Now go on and get going, we don't need others wondering where you are." He gestured with shooing hands.

Yona got up, grabbing her clothes as she got dressed quickly. The smell of shit and cum radiated off her as she walked to the door. "Thank you, professors. Yona will see you again next year."

Once the door was closed the pair looked at each other with big smiles. The two of them got dressed as quickly as they could to hand in reports to the Headmare. "So, how much do you think we can make off these pov angles online?" Galbrid started flipping through the length of the forty-minute video.

"I'd say more than what I gave her in cash. She'll never find out, with how stupid she is. I'm glad she came to us and offered sex for grades. Been wanting to plow one of these bitches for a while now, and even getting to take a shit in her mouth was even better." Hightide chuckled as he got his papers together.

"Well then, next year we'll use her much more for all the grades instead of just the final one. I think I can work on getting that zebra teacher to join in no problem. He always talks about big busty women." Galbrid finished putting his panty prize away in his briefcase as the two walked toward the door.

All that was left in the room was the puddle of piss and cum that had been from their sexual encounter. Yona, now a changed yak, from innocent girl to toilet slut, and two teachers who had found a new toy to be able to use whenever they wanted.

Author's Note

If you enjoyed this story and would like to see a sequel to it. Let me know in the comments or through PM if you don't want your name seen by others. As always you can show your support with a Thumbs up or Favoriting the story. I have spent a bit of time trying to make something with Yona, and this was certainly a good blend of two of my favorite things.