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This is a fairly long fictional story separated into a first act (more focus on sex) and a second act (more focus on story). Only the first act can be properly read without reading the second act. In regards to theming, both acts of the story mainly describe the gradual and sexual escalation of clueless or naive women. It quickly becomes quite extreme, non-consensual, cruel, and tortuous. It is definitely not for the faint of heart (however, no cannibalism, scatology, or snuff).
V. The level 4 of sister Mary

After a total of 52 days at the institute, sister Mary finally reaches all goals for level 4. Proudly, she shows father John that her ass can take a circumference of 24 cm (9.4 inches), a flexible dildo 35 cm (13.8 inches) deep and a stiff dildo 25 cm (9.8 inches) deep. Her pussy manages a circumference of 25 cm (9.8 inches) and a depth of 24 cm (9.4 inches). Like last time, she wants to have sex with father John immediately, however, this time she is treated to two loads of cum that she cherries as much as possible.

Afterwards, he pulls out a large syringe and injects each of her breasts with a lot of some strange liquid. Then, he pulls out the heating guns again and further expands the size of her tits. Sister Mary tries to hide the fact her breasts feel a bit too tight, as she does not want to look weak in front of her beloved father John. Nonetheless, she is breathing heavily once her tits are fully expanded. He feels her breasts and checks for any complications, while she smiles with a slightly worried look.

“Perfect shape... the implants work flawlessly. We can continue like this. You are now at 1500cc, but they can be expanded up to 2100cc, as they are now.”

“Father John, how large are they supposed to be? They are already massive.”

“It depends a bit on your breasts. Your tissue is very stretchable and sturdy. So far, I don’t see much of a limit yet.”

That is not the answer she was hoping for. He cools down her breasts with water and exchanges the rings in her nipples and clit with studs. Finally, her blue ribbon is exchanged for a purple ribbon, which she celebrates with a little dance.

On the way to her new chamber, father John explains that her chamber will have a larger carpet as well a window with a view to a park.

In the room, she finds an outfit that she is instructed to wear. It includes furry ears, long stockings with paws at the end and long gloves with paws at the end. She will have to receive every master this way and only remove it on their command.

She has worn such clothing occasionally and is already curious about a missing item. While she puts on her clothing, father John has already opened a wardrobe.

“Father John, is there going to be a tail?”

“Yes, try this one.”

“Oh, that tail is shorter than the last one, father John.”

“It is 35 cm (13.8 inch) long. That is probably the right size for you.”

She gives him a puzzled look. Why is it the right size? Her eyes widen when he turns the tail around. On its other end, instead of a plug, it has a long flexible dildo. It starts with a circumference of 24 cm (9.4 inch) and tapers slightly down to a circumference of 7 cm (2.6 inch). He hands her the massive toy and tells her to insert it. It takes her quite some time, as the toy challenges her both in depth and circumference. After she finally gets it in, she wants to stand up, but he stops her.

“No, when a master is with you, you go on all four unless told otherwise.”

She slowly goes back down to her knees.

“Will I have to walk forever on all four, father John?”

“No, there are three scenarios, where you can walk upright. The first one is, when the master allows it. The second one is when there is no master. The third scenario is when your tail still touches the floor, even when you walk upright.”

“But my tail is too short!”

“Don’t worry, there are longer tails in this wardrobe.”

He opens both doors to reveal many tail plugs hanging there, with different lengths. Inside are tails of all kinds of sizes, even longer than 1 meter. However, on closer look, she sees that the plugs are not identical.

“Wait, what is with the plugs, father John?”

“Each tail plug has a flexible plug portion that is exactly as long as its tail on the other side. For example, this plug is 1 meter (39.4 inches/3.28 feet) long and it also has a tail that is 1 meter long.”

She is trying to process what he is saying. It can’t be what he means.

“I don’t understand, father John. It sounds like what you are saying is...”

“Yes, you got that right. When you can fit such a long dildo in your ass, you are free to move upright.”

“You mean this is even possible?”


She is absolutely stunned. She thought she had advanced so far, yet she encounters new, insurmountable goals. Sister Mary does not see herself ever getting this far. He notices her resignation and puts it in perspective.

“Don’t be discouraged. Such long tails are usually worn by level 8 or 9 sisters.”

This fact does not really feel encouraging to her. She does not think that she can measure up to all these challenges.

“We are not done, there is more that you need to do.”

He speaks into his device: “Bring in the basket.”

Sister Mary is getting nervous. What other torture device could he bring in next? Whenever she thinks it can’t get any worse, they find new ways to make it harder for her. She crawls to the basket and is shocked to find...

“Awwww, father John, it is a basket of puppies! One, two, three, four, its four puppies. They are adorable!”

“They are only 1 day old. Take good care of them. You are now their stepmother. Raise them and feed them.”

She already took one pup out of the basket and pets and kisses it all over.

“Ohhh, I will take such good care of them. Of course! What food should I give them, father John?”


“Oh right, they are still babies. They need milk.”

Father John says nothing and watches her not realizing yet what he meant. She is still petting the little animals and looks up at him, still not understanding what he means. After he glances at her tits for a second, she can put it together.

“You mean... my milk? Can I feed them like this?”

She looks at the pup for a while and then holds it to her left breast. The blind baby is smelling around, and stretches its head closer to her nipple. After a few licks, it latches on and starts sucking. Sister Mary is first surprised, but then pulls out a second pup and starts feeding it with her other breast. Her face beams with joy and she wholeheartedly smiles at father John.

“Good, they accept your milk. I suggest you lay them on the floor and kneel over them.”

She lies all four pups on the floor and arches over them while on all fours. They quickly latch on the massive tits hanging over them.

He speaks into his device: “Bring in the sire.”

The door opens and a huge wolf enters the room. Its shoulders alone are 1.2 meters (4 feet) high and his slow steps are accompanied by a deep and menacing growling. When he sees the pups, he makes a B-line for sister Mary, who is still on all fours with eyes open like a deer in the headlight.

“You should show him that you are feeding his babies.”

Barely daring to breathe, Sister Mary slowly grabs one of her tits and angles it up, causing milk to spray into the direction of the wolf. He sniffs and curiously gets closer to her. She is shaking, but has to hope that the beast understands. With her huge breasts and the massive dildo in her ass, she cannot run or fight.

The wolf sniffs close to her, licks her nipples and sniffs the pups. Maybe he understands that the milk is feeding the pups. She slowly lowers her breast, allowing a pup to latch onto. The wolf appears to calm down and sits down, towering over her and carefully observing everything. Father John watches from the side without much concern.

“Sister Mary.”

She whispers back at him: “Yes, father John.”

“It looks like he has accepted that you feed his cubs. But he does not consider you a mate. You are not a part of his family yet.”

“How do I make him my mate, father John?”

“You mate him.”

“... How do I make him my mate, father John?”

“You heard me, sister Mary.”

She looks at him, shaking her head, hoping there was a misunderstanding, but he nods back at her. There wasn’t. She is sighing, trying to come up with a plan. Maybe she should start with physical contact.

Sister Mary reaches out at him, carefully touching his paw. Then, she slowly strokes his front leg and continues towards his chest. While caressing, she looks over to father John one more time, hoping for a different response, but he just gives her another nod. She takes another breath, gathers courage and lowers her hand until she feels his groin. However, the beast is wary and backs off, staring at the unknown milk provider.

She needs to lure him back to her. Sister Mary grabs her breast again and rubs her nipple until it sprays milk towards the wolf, who decides to approach her again. After some sniffing, he licks her nipple a bit and eventually starts sucking. Carefully she lets go of the tit and uses her hand to slowly reach for his cock again. This time, he does not back away and she can stroke him. After a while, she gets a response and a shaft extends outside into her hands until it reaches a length of 25 cm (10 inches).

This is as far as she had planned. Now she is stuck, stroking his cock, while the pups are still sucking on her tits. So, she grabs his hind legs and pulls him slowly towards her face.

Is this really happening? What if he bites her? She just stops thinking, closes her eyes and takes his cock in her mouth. The wolf is taken back for a moment, but calms down when she carefully massages his cock her tongue. She speeds up ever so slightly in order to please the beast panting above her. After having gained enough of his trust, she pulls out and gently pushes him to the side until he stands behind her.

As she can barely look behind herself, she tries to invite him by pulling up the tail, arching her back, and wiggling her butt in front of him. His panting stops and he jumps up on her, his claws scratching her back, trying to hold onto the furless human. Without looking, she reaches around in the air until she gets a hold of his cock and guides it into her pussy. Once he is in, he gets to work and starts thrusting. The large toy in her ass tightens her pussy, making it hard to insert anything. But the beast is strong and overcomes any resistance by force.

The large wolf thrusting into her tiny pussy should scare her, but she is actually relieved that he does not try to attack her. This is the first time she has sex with an animal. The wolf seems to love her human pussy and thrusts furiously. It’s not easy for her, but she can take it. She likes the way he has his way with her. No games, just instinct. She can’t believe it; he loves her tight little pussy. Such a big beast, but she can please him. The pups keep sucking her tits, while the little girl gets ravaged by their father, and it feels so good. Her breathing intensifies and gets faster, while she tries to hold steady against the powerful thrusts. Eventually, her breathing stops as her body tightens, experiencing a powerful climax. The wolf soon follows suit and comes inside her pussy.

The pups had already stopped sucking, allowing sister Mary to finally sit up and relax her back. Father John walks up to hear and hands her a cup.

“Good job. It seems the sire has accepted you as a mate. Here, try to not get anything on the tail.”

She hesitates for a moment, but squats over the cup and empties all the seed into the cup.

“Father John, is his name “sire”?

“No, that is what you call a male dog that is the father of pups.”

“And what do you call the mother?”

“The mother of pups is called a ‘dame’”.

She smiles.

“So that makes me a dame then, father John?”.

“No, you did not give birth to them. You can consider yourself just a female dog, a bitch. You are his bitch now.”

She looks slightly disappointed at her new title, but her attention is then shifted to the cup, holding about 50 ml (1.7 ounces) of wolf cum. She glances shortly to father John, who nods again, just as she expected. The eyes are closed, and everything goes down the hatch.

Father John then takes the wolf and attaches him to a leash that is hooked to the wall. Next to the hook is a second bed, which is a bit smaller than her main bed.

“Sister Mary, this is the bed for the sire and the cubs. The big bed is for the masters. You can sleep in either of them, I don’t really care.”

When she crawls onto the big bed, the movement reminds her of the huge toy in her ass. She still has so much stretching to do.

“Father John, what are the requirements for level 5?”

“Your ass has to take a circumference of 28 cm (11 inches), a soft dildo to a depth of 50 cm (19.7 inches) and a hard dildo up to 30 cm (11.8 inches). Your pussy has to take 30 cm (11.8 inches) in circumference and 28 cm (11 inches) in depth. As a level 4, masters can fist your ass and pussy and can piss into your ass.”

With all that information dumped onto her, he leaves the room. After a while, she remembers that she can stand now and hops off the bed. However, she quickly realizes that her sphincter and her guts are struggling while stretched to such an extent. But she doesn’t remove it and instead slowly waddles to the bathroom in order to clean herself for her next master.

“Good morning master, what can I do for you?”

“Well, for one, you can shut up, because a dog does not talk.”

Sister Mary lowers her head and mutters a small yelp. She now remembers this master, as he was the one that had stuffed her ass with balls, which she almost did not manage to get out anymore.

This time, she very dutifully performs all the orders he gives her, regardless of how much her ass struggles. After fetching the ball three times, he praises her.

“Look how fast you have gotten. You start off so quickly. Let’s see how fast you truly are. Sit in front of me and face the wall.”

She positions herself between his legs and prepares herself for watching the toy flung into the room. As soon as the ball goes flying, she sets off, just to smash into the ground. The master had grabbed her tail firmly, causing her to trip. Her ass hurts from the sudden impact and she lies on the ground, holding her ass.

“What is the matter? Get me the ball, you dumb bitch!”

She gets back on all four and gives him a puzzled look.

“Don’t look at me. I’m not the one holding onto you. It is your ass clinging to this tail. You have to let go of this toy if you want to get the ball.”

Her breathing accelerates nervously, when she realizes what he wants. He wants her to rip out the toy deeply logged in her ass. Sister Mary crawls forward and pulls with all her strength, while somehow trying to loosen her ass. Her sphincter stretches and stretches until the long flexible dildo pops out in one swift motion out of her ass, causing her to collapse into a fetal position holding her stomach.

The toy was folded up inside her intestines. Pulling it out so quickly caused her a sudden internal pain. But she knows that she can’t stay on the ground, rolls back onto all four and stumbles in a disoriented state to the ball, picks it up by her mouth and somehow makes it back. She pauses for a moment, but manages to get back into a kneeling position, feeling that her ass still has not fully closed yet after the sudden ejection.

“Good girl, you got the ball! But what is a dog without a tail? Let’s get it back in.”

The master brute forces the tail back into her ass, gives her a slap on the cheek, grabs her tail and throws the ball again. It does not get easier when she has to yet again rip the toy out of her ass, running to get the ball. But she bravely keeps sprinting in order to fetch it as fast as possible.

After the fifth time, he finally stops throwing the ball, and inserts his dick in her gaping asshole. However, instead of fucking her, she can feel her insides filling up with liquid. What is he doing? Oh no, he is pissing in her ass.

But at least she gets to catch her breath while she is sitting still, acting as his toilet. After he is finishes, he pulls out and she clenches her ass shut to not let anything seep out.

However, he proceeds to push the tail plug against her ass again. She can’t object, because she is just a stupid dog, so she tries to loosen her ass in order to let the toy inside. Unlike the previous four times, he is inserting it very carefully and slowly. Not because he is worried about her wellbeing, but to make sure, his piss does not accidentally drip out. After minutes of working inside her ass, her sphincter closes around the flare of the tail plug. With her guts feeling so full and sore, she tries to move as little as possible.

“Now ride me bitch.”

Her master lies on the bed and beckons her to come up. She crawls up and inserts his dick into her tight pussy, starting to grind against him. Her insides are ballooned up and object to any movements, but the young girl ignores her body in order to please the master.

Looking at her perfect tits swinging back and forth, he can’t help but start sucking on them, arousing the girl to the point where she is speeding up. Moving up and down on his cock causes the toy in her bowels to tear on her sore intestine, but grinding against her master increases her pleasure to the point where the pain can be ignored. She rides him harder and harder and after coming twice herself, she is rewarded with a mouthful of cum.

“Now, that is a good girl. But I think you need to pee right? I think you deserve to go for a walk, what do you say?”

She does not know what he means and just cocks her head with a puzzled look.

“I think you may like it. Let me see your tail wag. Come on, girl!”

She musters a smile and waggles the tail in her aching ass. He hands her a leash with two ends and instructs her to attach the leash to her own collar and one of the sire, while he leaves the room, to soon come back fully clothed. He takes the leash and goes ahead through the door for the masters.

Sister Mary is reluctant at first. She never went through this door before. She only knows the backdoor to the other facilities. However, a stern pull on the leash discards her reservations.

They walk through a fitting room and soon get to a main hall with beautiful decorations and lighting. After a while, they walk through a door and reach the outside with a nice park. She has not been outside since her rite of passage and slowly takes in all the sensations, breathing the air, feeling the grass and hearing the birds.

The master unleashes them both and lets them roam around. The sire runs off immediately, but sister Mary can only trot slowly behind, struggling on all fours, with her swinging tits and filled ass. She looks around and sees other masters walking around with sisters and wolves, most of which are roaming around freely as well.

Her master tells her to find a tree to pee on. She walks up, pulls out the toy and releases her master's piss against the tree. She groans from the relief and enjoys her empty ass for a moment before she pushes the toy back inside.

After crawling around a bit more, she notices that some of the wolves have started to run to the tree and to smell. Suddenly, three wolves run towards her, smell her piss-soaked ass, and wrestle her to the ground. She can barely get up, before one of them has entered her pussy. Before she can realize what is going on, another cock presses against her lips.

She tries to resist, but the powerful animals hold her down easily. When one of them starts to lightly bite her neck, she gives up resisting and lets them have their way. Another wolf that attempts to mount her head is calmed down by sucking off his cock. Since he keeps thrusting too hard, she holds his hind legs and instead moves her head, gently massaging the large shaft. This relaxes him and he allows her to please him.

They stop biting her and allow her to establish a rhythm. After a while, she swallows her first load and turns around sucking off the one that fucked her pussy. In the meantime, the next wolf begins plowing her pussy. With a bit more control over the situation, the initial shock is gone and she gets to enjoy the fucking a lot more. Eventually the wolves make her come a few times and she manages to catch every load with her mouth.

However, sister Mary gets exhausted after a while and does not know whether the wolves would accept if their orgy comes to an end. She has no authority, but her master does. After serving six wolves, she makes use of a short break and crawls as fast as she can to her master, who is just grinning at the shy young girl.

“Haha, why are you sending such mixed signals, my little bitch? These wolves look for mates by marking the territory with piss. Can you blame them when they take you up on the offer?”

She crawls behind him and cowers behind his legs. But luckily, her sire came back already, and they can go back inside.

Once the master has left, she chains her sire back to the wall and hears the pups howling for more food. Sister Mary feeds them while lying in bed together with her sire. Her ass and pussy are still hurting, but after a few minutes of resting and nipple stimulation she gets horny again. When the monitor informs her that the next master is about to appear, she gets herself ready to receive him.

Most of the masters this day make her fuck the sire, to which she happily obliges. Other than that, she gets fisted and milked a lot. For dinner, she gets her meal as well as a big bowl of food for her sire. As expected, she gets no food for the pups and will have to feed them with her milk.

The next few days, when she is stretching her holes, she notices that she can already insert 40 cm (15.7 inches) of the flexible dildo into her ass, but only 37 cm (14.6 inches) of the next larger tail plug. Even though the tail plug is tapered, the end portion is still quite thick. That is when she realizes that she will have to stretch the diameter of her intestines deep inside as well. Therefore, she focuses mostly on the next larger tail plug, as she can effectively train her sphincter, her insertion depth as well as circumference of her deeper intestines.

When she goes to bed, she struggles with two problems: The pups keep waking her up in the night, demanding more milk and the massive tail plug is incredibly uncomfortable to sleep with. She solves the pup problem by sleeping in the bed with her family, which allows them to just drink from her while she is sleeping. She finds no proper solution for sleeping with the long toy in her ass and eventually endures it long enough for the sleep to overpower the discomfort in her guts.

After a week (a total of 60 days at the institute), her stretching progress has slowed down in some regards. Her ass can now take a plug with a circumference of 25 cm (9.8 inches) and a length of 40 cm (15.7 inches), but she starts to struggle with rigid depth. Her pussy can take 26 cm (10.2 inches) in circumference, but is still stuck at 25 cm (9.8 inches) depth.

On the other hand, her pups made quite the progress and gained a lot of weight and subsequently more appetite. Sister Mary still produces more than they can drink, but their hunger is still increasing. Other than that, they are easy to handle, as they can’t run yet, but they will soon need leashes.

Today, her master has just filled her ass with piss again and plugged her with the 40 cm (15.7 inches) tail. At the park, the sire stays with them when they reach a tree and the master teaches the wolf to hold the tail in his mouth while sister Mary to tear it out of her ass again. After she released all the content against the tree, the master orders her to make the sire lie on his back and to insert his cock into her ass. Soon after, the entire shaft is buried deep inside her ass.

“Good girl. Now continue until his knot is in there as well.”

Sister Mary looks a bit confused. Does he mean that big red ball at the base?

“I thought those were his balls, master.”

“No, it is his knot. It allows him to cling into his bitch. Go ahead now, don’t make him wait.”

The knot already swelled to a circumference of 26 cm, which is almost larger than her limit. It takes her a lot of pressure to compress the knot with her sphincter until the largest part finally passes through. However, when her ass starts to close behind the knot, her guts are struggling with the depth. Sister Mary had noticed before how stiff the cocks of the beasts are. While human dicks can bend a bit in order to accommodate inside her, the one in her ass is hard as a stick. She can’t say what the problem is, but her gasping and holding her stomach speaks for itself.

“Is my little girl struggling? It’s not the same as the flexible plug, right? Did you know that canines have a baculum?”

Sister Mary shakes her head while frantically trying to align her body with the cock impaling her.

“It is a bone inside the penis. It guarantees that it is always hard. Isn’t that great? But it also won’t yield to your body. Your soft insides have to yield to it instead.”

Sister Mary is stuck between two uncomfortable positions. With her sphincter now having swallowed up most of the knot, she can’t pull out anymore, but can’t fully insert the shaft either. Her legs try to push her up to avoid the length of the cock, but her ass quickly pulls her back down again. Eventually, she manages to push herself up enough to open up her sphincter a bit.

By pulling out, she manages to get a little bit of leeway to move. After some trying, she notices that she can somehow wrap her intestines on his cock gradually by some circular movement of her hips, which requires her to poke herself repeatedly in the guts. After a long time of torture for herself, but enjoyment for the master and the sire, she can finally sit on the whole shaft.

She sits down and catches her breath and examiner her surroundings. The long insertion procedure gave surrounding wolves enough time to sniff her out and gather around her. By the time she got her sire’s dick entirely in her ass, around 10 wolves have gathered, but for some reason still waiting and watching. When sister Mary has caught her breath and found a comfortable sitting position, she nods to her master. She was worried at first. But now that she is more comfortable, feels pride in how she is able to take her sire completely in her 18 year old ass. What a good mate she is. However, her pussy has been empty for a long time and she is yearning for sex.

The master steps back and the wolves immediately jump at her. The first one jams his dick in her pussy and starts ravaging her. The other wolves stand around at first, but once sister Mary finds a good footing, she whistles one of them over and starts sucking him off. After swallowing his load, she guides the wolf in her pussy to her mouth and drains his balls as well. Her slit stays vacant only for a few seconds until the next beast is mounting her.

Sister Mary had many wolf orgies before and has grown to enjoy pleasing these powerful beasts. She relishes in the new sensation of being able to handle three of them already. After a while she can feel her sire come in her ass, which pushes her over the edge and causes her first of many climaxes to follow. With her body experiencing such excitement, it doesn’t take long for her breasts to start shooting streams of milk. Wolves that are still waiting their turn rush over to catch it and proceed to suck out the delicious milk directly. They are rough with her delicate nipples, but she loves it.

However, after a while, she notices more tension on her tits. When she looks down, she realizes that they are expanding in the heat of the sun. The growth does not stop until the implants reach their maximum volume of 2100cc. If she wasn’t that horny, it would probably hurt. But she is too busy getting fucked to bother.

After an hour, the master steps up to her and all the wolves disperse again. Still with her sire’s cock in her ass, she sucks a final load out of her master and is allowed to get up. However, she points at her sire and then at her stomach, gesturing how he filled her up.

“Your ass is filled with his cum?”

After she nods, he makes her get on all four before he pulls out. He plugs her ass with the tail and they go back to her chamber, where she finally gets to empty her ass into a cup. Judging by how full it is, she estimates that he probably came four times inside of her. She empties the cup with several big gulps and her master leaves her alone.

Sister Mary learned two things today: Firstly, she needs to be careful if she is outside on a very hot day, as her tits may expand to their full size. Secondly, with some alignment she can get even stiff objects into her ass.

Her sire also learned two things this day: Firstly, that his bitch prefers if he comes in her mouth. And secondly, with enough force, he can pull out her tail and fuck her ass as well. He applies both a lot more from then. Sister Mary does not mind getting ass fucked and welcomes the training for her ass, but ripping out her tail always hurts. The sire never cared to learn that.

For the next days, the masters made the wolf fuck her ass a lot, as they enjoyed seeing sister Mary still struggle with it so much. It took her two weeks to be able to take him full force. However, all the training paid off well, as she now is also able to entirely take the trans sisters with their 30 cm (12 inch) cocks in her ass as well. However, the brothers with their 36 cm (14 inch) cocks were just not possible yet.

The pups are growing faster now as well. They each gain a weight of about 350 grams (0.77 pounds) per day. Their hunger has gotten so large that they had sucked sister Mary almost completely dry. This had pushed her tits to increase total production to 10 liters per day. Since they are well fed, they reach a weight of 10kg (22 pounds) already after a month and can outrun their mother.
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