Incestual Sexing

by MagicalPony2099

Rating: mature
Tags: Romance, Sex, Alternate Universe, Original Character, Porn, My Little Pony: Friendship is Magic, Fetish
Length: 3788

Brother and sister does incest sex to each other.

Nate McTonny and his sister Kate McTonny are identical twins, being born with no mane and tail are currently 9 years old. They want to try to do more for their relationship and decided to have sex for the first time. Read and find out.

NOTE: THIS IS A ONE CHAPTER STORY!

Also On-Hiatus until further notice.

Contains: Foalcon, Incest, Estrus, Cum Inflation, Vaginal, Oral, Deep Throat, Impregnation, Birthing, Hyper, Watersports, Urine Inflation, Cum In Bladder, Bladder Inflation, Urethral Penetration, Urine In Balls, Urine In Bladder, Urine Exchange, Ball Inflation, Omorashi, Full Bladders, Bursting Bladders, Urine In Womb, Drinking Urine, 69ing, Babycon, Masturbation, Breastfeeding

Cover art is made by me.

Published 2022-07-06 15:00:01 UTC
Last updated 2023-06-21 03:34:14 UTC

The Only Chapter(TBU)

Nate McTonny is a 9 year old earth pony colt that has a lime green coat, has blue eyes, and has no mane and tail. His cutie mark is of a pole with a money sign. He's the brother of his twin sister Kate McTonny, who is a 9 year old earth pony filly that has a lime green coat, has blue eyes, and has no mane and tail. Her cutie mark is the same as her brother.

They were born in Ponyville on March 29, 917 ANM(After Nightmare Moon was banished to the moon). Around their birthday is during Estrus week.

When they turned 5 years old, they ran away from their home of Ponyville with all of their mother's money into the big city of Manehatten. They're currently living in a apartment complex that they bought with the money they earned from working at a strip club for 4 years. They work the night shift there.

After hearing news of their mother's death, they were only 7 years old at the time, they were happy that they were finally free with no more family members in their family.

They were the youngest to ever get married at the age of 8, on their 8th birthday no less.

Its the next day after their 9th birthday, just a day after they celebrated their 1 year anniversary of being married.

They were at home in the apartment complex that they bought just 2 days ago.

Nate was reading a very interesting book that he got from the Manehatten library. The book he's reading is about the plant life and their connection to the ponies around them, when he felt something touch his shoulder. He lower his book to see his wife/twin sister Kate.

"Yes Kate?" Nate asked looking Kate in those cute blue eyes of hers. She has this beautiful smell that he's smelling.

She looked at him with a lusty look in her eyes. "Bed, now." She needed to be rutted right now, because her pussy was wet. She's currently on her estrus cycle.

She was giving this 'I wanted to be rutted right now' vibe, because he smelled her scent. Her scent was driving him wild.

"Okay Kate." He said putting his book down. He got off of where he was sitting and went with Kate to their bedroom, his cock was coming out of his sheathe. He was born with a full grown stallion cock of 2 feet when erect. Now he's 9 years old, his cock when erect is a whopping 6 feet in length.

Earlier today during breakfast, both Kate and Nate drank alot of orange juice, and now its after 3PM. Both of their bladders were full, ready to burst.

Just a year after they ran away to Manehatten, after drinking alot of milk for breakfast, they both discovered that having really full bladders that was ready to burst was their fetish. Ever since then, they discovered new ways to do brace their watersports fetish.

Now in their bedroom, with him with a twitching, throbbing, fully erect cock and a full bladder. She taken his whole cock inside her before and now her pussy's wet from her estrus as well as a full bladder. She needs his cock inside her. The thought of his cock inside her made her clit wink. A string of pussy juice came out of her. Also the thought of his urine inside made her start to droll. She needs his urine, the taste of it. Well, not taste because of how long his cock is, it goes straight to her stomach. And get this, they were born without gag reflexes, so that his cock can easily go down her throat without gagging.

Both of them got on their bed...

--

After Nate had just peed inside Kate, she started to pee inside his mouth. They were 69ing while on the bed.

--

Nate was close to climax, his cock was beginning to flare inside her womb. He then came inside her awaiting womb, making Kate moan out his name.

Kate felt the first spurt of cum inside her womb and then the next spurt and so on and so forth. She felt her womb getting filled to the brim with his cum.

--

11 months has past since Nate impregnated Kate and they're glad that the foal Kate is pregnant with is female. They both had a special fetish of impregnating the female baby foal that just been born.

Right now both of them are in the hospital for the birth of their foal because Kate's water broke and has been trying to hold the birth of their foal in.

Kate's pussy was leaking vaginal fluid from trying to birth this foal. She screamed as she felt her foal trying to come out of her.

Nate was holding her hoof as she continue trying to get their foal out of her leaky pussy.

"Just keep pushing." Doctor Oli said. She was in front of Kate's leaky pussy. Kate continue to scream as her pussy trying to push this foal out of her.

This went on for about a little bit until Doctor Oli saw the head of the foal. "I see a head, just keep on pushing this foal out of you."

Kate kept on pushing this foal out of her, she didn't suspect to become pregnant with a foal at the age of 9 and birthing this foal out of her close to both her and Nate's 10th birthday. She continues to scream.

Nate just kept on holding her hoof as Doctor Oli saw the foal almost out of Kate's pussy. "You're almost there, your foal is almost out of you."

Kate kept on pushing until they heard the sound of crying.

Doctor Oli look at both Kate and Nate with a smile. "Your foal is out." She looked at the just born foal. She saw the foal looked healthy. The foal's coat color is blue, has a yellow mane but no tail, and has a pussy. Doctor Oli smiled at the foal. "Your foal is a healthy female earth pony." She looked at Kate and Nate. "Do you want to hold your newborn filly?" When she just asked that question, the filly just started peeing at her.

Newborn foals pee after they're just born, whether their male or female. Doctor Oli just stared at the peeing newborn filly. The sound of 'psss' filled the room as the filly kept on peeing, making a puddle of piss on the floor.

The filly finally open her eyes for the first time since she was just born. Her eyes were a pink color. She looked at the pony in front of her with a curious look. Her head tilted to the right side.

Doctor Oli looked at the filly. The filly's eyes were a beautiful pink color. Then looked at the parents of this newborn filly. "Well, I think..." The doctor looked back at the peeing filly. The filly's little clit winked as the filly kept on peeing. "...you can guess on what to do with her. Also a name for this newborn filly. What do you want to called your newborn filly?"

Kate and Nate looked at each other, then back at Doctor Oli, and nodded. Nate first spoke up. "Well, we like to name our newborn filly..."

"Jane McTonny." Both Kate and Nate said at the same time.

Doctor Oli nodded. "Okay, your newborn filly will be named Jane McTonny. What do you want to do with your foal now?" She looked at the both of them.

With the knowing looks of Kate and Nate as they decided to. "Impregnate our daughter."

The smell of urine from Jane was making Nate's hyper 7 foot cock fully erect.

Doctor Oli's pussy winked as she was getting turned on for wanting a newborn filly to be impregnanted. She wasn't on her estrus cycle, but she's damn well felt like it.

Jane finally stop peeing. Drips of her urine dripped out of her pussy as she was finally done peeing. But her pussy became wet as her little clit winked in and out of her pussy. She didn't know what this meant at all. All of this weird feelings was brand new to her.

Doctor Oli just gave the foal to Kate. "Here you go Mrs. McTonny, your foal." Kate grabbed her daughter and looked at her. She smiled at her filly. "Hi there, I'm your mommy. And this..." She showed the filly to Nate. "...is your daddy."

Nate just smiled. He wanted to buck a foal in this filly right now that his cock twitched and throbbed. The cum in his balls also wanted to get this newborn filly pregnant as well. They demanded to be sent to the filly's egg to impregnate it. Nate felt his balls twitch and heard the cries of his cum in his mind.

"Kate, I think... you're not gonna believe this but, I think my cum wants to be inside our daughter's womb right now." Nate said looking at his wife.

Kate looked at him with a surprised look on her face, she didn't think that Nate's cum became alive during these 11 months of being pregnant with their foal. But then sighs. "Okay."

Jane just look at her parents in confusion. What were they talking about. Her freshly newborn mind couldn't come up with anything at all.

Doctor Oli has a special relationship with Kate and Nate. When she's off the clock from being a doctor; she, Kate, and Nate are in a polyamorous relationship. With Nate being lead husband for his wives.

And right now, Doctor Oli has taken off her work clothes and started to masturbate, rubbing her pussy with her hoof. Her clit wink every time her hoof rubs it. Vaginal liquids getting on her hoof as she masturbates.

Nate lying on his back with his 7 foot long erect cock in the air, twitching and throbbing with precum coming out of his urethra.

Kate held her daughter in her hooves. She brought her face to her daughter's unused virgin pussy and started to lick it. Tasting the leftover urine from earlier. It tasted bitter, but she liked it. She used her tongue to taste inside Jane's unused love canal.

Jane felt these new feelings that she never felt before. Her cheeks flushed red as she's being oraled by her mommy. She was only 10 minutes old but she never felt this excited before. Her pussy clamped on her mother's tongue as she felt getting close to her very first orgasm ever.

Kate felt her daughter's pussy walls getting tighter as about to experience her first orgasm. She let her tongue touch her daughter's g-spot.

That did it. Her daughter let out a scream as her pussy went through her very first orgasm. Her pussy gush out fillycum on her mom's tongue.

Kate tastes her daughter's fillycum on her tongue, it was very sweet that she ever tasted before. Her daughter's fillycum taste like cherries. She brought back her tongue inside her mouth. She swallowed her daughter's fillycum.

Jane's face was flushed red as she experience her very first orgasm. She panted as her orgasm subsided. She never felt soo relaxed before.

Doctor Oli experience her orgasm after watching Kate did oral sex on her daughter. After her orgasm subsided, she got back up on all fours, her legs wobbled from that orgasm, but didn't clasped.

Nate was just waiting patiently for his daughter to ride his cock inside her. His cum really demanded for his cock to be inside his daughter's pussy. "Kate, my cum is getting angsty for my cock to be inside our daughter's pussy right now."

Kate looked at Nate. "Hold on Nate."

Kate kissed her daughter on the lips for a few seconds. After that, she let go of the kiss. She sighed happily. "Okay Nate, you'll get to finally buck our daughter her very first foal or foals."

His cum heard that and cheered in unison. "My cum is happy. Now get our daughter onto my cock and push inside her pussy. I want to be her first."

Kate did just that. She brought her daughter over his cock where her pussy is at and let his cock inside her virgin pussy.

Jane felt her vaginal lips open from her dad's cock being pushed inside her. She felt her slick walls open with cock meat inside her. Even after being born, she felt like a natural. Like her special talent is being a breeding mare for any colts and stallions.

"Oh look Nate, our daughter is a natural. She'll being a great breeder for our job at the strip club. But lets put a foal inside her first before letting others buck foals inside her." Kate said ecstatically.

Jane felt something bump her unbroken cervix. It was her dad's cock. Not even a couple of inches in and she felt full of cock inside her. She felt his cock slide out of her, she felt empty. But then she felt his cock inside her quickly and let out a scream as her cervix teared open. Tears rolled down her face as fresh virgin blood leaked out of her pussy. His cock was inside her warm womb.

"Oh my Celestia, she's bucking tight!" Nate groan with gritted teeth. "I can't believe I'm inside her womb already. I don't think I can last longer." He felt his flare grow inside his daughter's womb. He was that close to cumming. And after a few more seconds, he felt his balls extract and let out a loud moan as the first burst of cum leave his cock.

His cum were ecstatic to finally being inside the womb of Jane McTonny.

After a few more bursts of cum left his cock, he felt his cock soften and with a pop, cum fell out of her pussy.

His sperm was swimming towards Jane's egg.

'Come on brothers and sisters, lets get this filly pregnant. I know we were getting impatient inside Nate's balls, but we finally get what they wanted.' Lets name this sperm John. 'A sister or brother for Jane or even twins for that matter. Now let's do this!!!!'

While all that was happening, Nate was kissing his daughter on the lips like Kate did earlier. "We love you Jane and I hope you'll be a great breeder."

Jane is 17 minutes old and a light shown on her flank. When that light disappeared, a loud gasp was heard from Nate, Kate, and Doctor Oli.

They couldn't believe their eyes that Jane McTonny, a 18 minute old filly, got her cutie mark. Jane's cutie mark is of a cum filled womb, meaning of being a natural born breeder.

Doctor Oli looked at Nate and Kate with a smile. "I think she became pregnant when her cutie mark appeared. So that means that Nate's sperm reached Jane's egg and went inside it. Congratulations you two, your daughter will be a mother. So I suggest for you to tell your boss that you can't come in for work for the next 11 months until your daughter gives birth to her foal or foals. Also I think your daughter needs your milk Kate."

Kate notice that her daughter needs something, so she grab Jane and put her in front of her crotchboobs and began to breastfeed Jane. She felt her nipple being sucked on. Her milk was being sucked out of her. "We will Oli Hanginton."

Yes, that's their main doctor's name. Doctor Oli Hanginton is her name.

After awhile, Jane stop sucking her mom's teats. She needed to be burped, so Kate picked her up and pat her back with a hoof until she heard a loud burp from Jane.

Nate's eyes widen. "Holy Celestia! That was a loud one."

Jane yawned as she was getting tired. She felt her eyes getting heavy as she begins to fall asleep.

Doctor Oli Hanginton looked at Nate and Kate. "Well, I think its time to put this one to bed. I just have to do a couple more tests to be sure your daughter is a healthy filly."

They both nodded and Kate gave Doctor Oli their daughter to do a couple more tests on her. Then the doctor left the room.

Kate looked at Nate with a smile on her face. "I'm just really happy to have Jane as our daughter and soon to be a mother herself in 11 months."

Nate nodded at her. "Yes Kate, me too." He smiled as well.

After awhile, Doctor Oli Hanginton came back inside the room with Jane McTonny in a blanket wrap. "Well..." Oli gave Kate their daughter back. "...I did the tests on your daughter and turns out, she's healthy. Even the pregnancy test turned out to be positive. Your daughter is gonna be one great breeder."

Kate looked at the doctor. "Yeah I know and thanks."

Oli added. "I'll even quit being a doctor for Manehatten Pediatrics and become your own personal doctor at your home instead so that I can be with you two in your own home."

Both Kate and Nate were shocked to hear that their wife Oli Hanginton, will quit being a doctor for this hospital and become their own personal doctor so that she can be with them at home. They both looked at Oli and nodded. "Do it."

Oli just smiled. "Thank you, you two. Now I'll just write up on why I'm quitting and just go home to your place." She went and left the room again to do just that.

Kate was getting tired after everything she went through, from giving birth to her daughter Jane McTonny to waiting on Oli Hanginton to come back. "I'm gonna take a nap Nate, night."

Nate just smiled. "Night Kate." He kissed her on her forehead and she fell asleep.

Nate just sighed. His eyes were getting heavy as he fell asleep as well.

A couple of minutes later that Oli Hanginton came back in the room to see that Nate and Kate as well as Jane were asleep. She wrote her quit notice on why she's quitting being a doctor here at Manehatten Pediatrics on her work desk. She just let them stay asleep for the night. They were on the 3rd floor of the building. She smiled at them, they were soo cute sleeping together, that she turned the light for the room off, went out the room and close the door behind her.

She sighed. I know I'm gonna miss working here, but it's for Nate and Kate. She thought as a tear roll down her face. She should be happy that she's gonna be with Nate and Kate, but working for Manehatten Pediatrics for 15 years but deciding that she finally called it quits being a doctor here has made her sad. But being sad won't do her anything.

But something inside her made itself known. Her bladder, it was full. She felt a ping in her bladder telling her to 'empty me'. There was even a bulge where her bladder is at. It was that full. "Okay, okay. I'll empty you." She told her bladder to stop notifying her.

She made her way to the restroom and went inside it. The 3rd floor restroom was unisex anyway. So, she made her way to the one of the stalls, but she decided against that. The restroom was empty, nopony was inside it. She was all alone in there, just her.

And because of after she leaves with Nate, Kate and their daughter Jane to their home, she wants to do something that when Jane was peeing earlier after she was born, she wanted to just drink up her urine, she wanted to taste her urine, but couldn't. So now because of her really full bladder, she's now got that chance.

She laid down on the cold tiled floor, bend her lower back so that her pussy is facing towards her face, she then opened her mouth as she covered her pussy in her mouth and she let out a sigh as she relax her bladder muscles. Her breath on her pussy made her clit wink. She felt her urine came out of her urethra and straight into her awaiting mouth. Her urine touch her tongue, her eyes widen as the taste of it was bitter, but she liked it. She started to swallow down her urine into her stomach. She kept on swallowing down her urine.

Her bladder was close to empty so the flow of her urine came to a slow trinkle and after that the flow stopped leaving only droplets of urine out of her urethra into her mouth. She felt full from all of that urine in her stomach. She sigh in relief as her bladder was now empty. It'll fill back up later after drinking all of that urine.

But its been awhile since she had a orgasm. She never done oral sex on herself before, so she stick out of her tongue and into her wet pussy. She moaned as she lick the inside of her own pussy. Her clit winked as she kept licking the inside of her own pussy. She then scream in her pussy as her tongue touched her g-spot. She kept on licking until she was close.

Her pussy walls clamped down on her tongue as trying to milk it. After a few more seconds of licking, she let out a loud scream as her pussy gush out squirt after squirt of marecum into her mouth. Her own marecum tasted bittersweet, she loved the taste of her marecum. She orgasmed for a few more seconds until her orgasm calmed down.

She let go of her lower back and let it fall to the floor, straighten it back. She was out of breath from orgasming. She was tired from this, but somehow found the strength to get back up on all fours and walk right out of the restroom she was in. She went the main area of the 3rd floor and checked the time. She saw it was after 4 in the morning.

Might as well go to sleep on one of the waiting benches. She thought as she went towards one of the waiting benches that occupy the main 3rd floor area. She got on it and laid down on her back on them. As she laid down, she fell asleep.

Author's Note

I really hope you enjoyed reading this story. If not then, I tried.

This is the full chapter, you're welcome!