Tim was a red domestic cat, living in what might be the weirdest “family”. While family by blood, they have long turned into a debaucherous sex cult of inbreeding and pedophilia. Sometime long ago their family was normal, but one of their ancestors, or rather “the ancestor” as they called him now, decided to build a ginormous underground city using his incredible wealth and political influence. 
He had claimed it would be a utopia if the world ever needed in the case of an apocalypse. However when he caught his wife cheating he snapped and altered his plans. Having had urges that would disturb most people and certainly get him thrown in jail if he were to act on them, he had lost his outlet with his wife gone and an incredible opportunity in front of him.
So as the already secretive project was being finished he worked hard and erased most if not all evidence of it. After which without anyone being aware enough or able to stop him he took his still young children, a pair of female twins his now ex wife had birthed only two years ago, inside the secret city and locked it up. Being left alone and secluded from the world he began building up his new family.
Using the twins as his new wifes, he was able to live out his wildest fantasies and soon after they were old enough produced new offspring for his desires. Being isolated with his own twisted ideals and perversions, it was easy to create a cult around it as everyone born there, wastold from birth that what they were doing was the correct way and how they were supposed to act.
Without caring what would happen after his death, the ancestor had only installed rules and rituals that would suit his own twisted needs. So maybe even he would have been surprised by what kind of situation the little cat Tim was now in. Maybe even he would have put a stop to the situation if he were there, or maybe he would have enjoyed and encouraged it.
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Tim was sending his prayers to the ancestor as he was standing in front of the lottery waiting anxiously for the result. Having turned 12 only recently, he was finally seen as an adult in their community and had entered the lottery every time as soon as he could. Maybe this time would finally solve his massive problem. 
He had always been either left out or forced to be the bottom in all their plentiful orgies. All while watching his peers plenty of opportunities to lose their virginities the old fashioned way, he was stuck with a massive problem in pants. Due to the many generations of unethical inbreeding and dubious beauty standards there have been many mutations. Some have been celebrated as the will of the ancestor now more common than not, others detrimental to those affected. 
There were plenty of examples for sought after mutations in the current day, some even being so prevalent they have been accepted as normal. There were newborn girls with massive tits or boys with sizable cocks both rivaling adults. People who never seemed to grow physically mature. Newborns, able to take adult dicks without hurting and so many more mutations.
Most boys like him, with oversized cocks were often worshiped and had many women fighting over who could get their pussy stuffed by them. However his penis was so massive it was literally frighteningly big. While he had found fun ways to pleasure himself, with his cock easily reaching his mouth, there had been more downsides than upsides.
There had yet to be any woman or man, at this point he would take any hole, who was willing to even try to take his tool inside of them. Even as a toddler it was too big already, that at his own initiation it had only been one man participating in the lottery. To Timsdetriment the man had weird interests and mostly wanted the boy to fuck his urethra.
As was custom this man had become his father by rite and had continued to use Tims cock as a sex toy until Tim finally turned 12 and earned his freedom. To his fathers dismay Tim was now considered an adult and thus his father was no longer allowed to give consent for Tim.
Today Tim was praying more than ever that he would finally be chosen to initiate and then parent their newest family member. While he had already had plenty of chances as new children werent rare at all, with everyone fucking all the time and protection both forbidden and unavailable. This time the newborn to be initiated was very special to him. 
The girl to be initiated was his sister by blood, which gave him greater chances to be chosen, as the ancestor had decreed the closer in blood the better. While that was exciting on its own, there was also a greater chance that the girl might have the opposing gift which he had suffered. He was especially excited that he had a sister by blood since his mother even though she gave birth to him as young as she had no child ever since until now.
Unimaginable to most, here girls were able to give birth far before they even turned twelve, early pregnancy being one of the earliest mutations to manifest and is practically normal at this point. While the mutation usually allowed girls to become pregnant at a rather early age, there were still some outliers, his mother for example had only been turned three when she had him. 
However Tim was praying for a different mutation. Most came to call it extreme capacity, which as the name suggests, allowed even newborns to take unusually sized dicks. At first it was only a means of survival forcefully bred into their family, by the rituals decreed by the ancestor. However after becoming common to take regular adult dicks the term was used for something different. 
What he was hoping for was often associated with girls or boys who had a previous sibling with the mutation for an oversized cock. The affected newborns were able to take far more than others, often even being the perfect fit for that sibling. While it wasn't a guarantee especially with his unimaginable size, this was probably the best chance he would get any time soon.


Thinking about finally being able to fuck a cute little girl was already giving him a raging boner. He couldnt and wouldnt stop his arousal, even if he was already leaking massive amounts pre while in the middle of the crowd. While his erection was drawing stares it was due its unusual size rather than his hard on, as he was far from the only one showing clear signs of arousal. 
Then it was finally time to draw the name, the gong hushing the gathered crowd to listen to who was chosen. Tim was practically bursting with anticipation, unable to stop touching himself a little while eagerly waiting and praying. There was a brief pause like the world was standing still before the priest opened his mouth to speak. Then his name was called out loud and clear and his mind turned to chaos. While Tim was trying to stay respectful to the ancestor a sharp gasp went through the crowd as people turned and stared at him.
While he felt like celebrating the mood grew somber, as many clearly were expecting that the girl would not make it through the night as he was clearly eager to have his way with her. In the current age, most had forgotten how the mutations came to be that allowed most of them to survive their initiation. So they were filled with horror as their minds imagined what might befall the newborn in front of them.
As the murmurs slowly grew about stopping the proceedings as this clearly could not be what the ancestor had wished for, their priest had to stand up in defense of the rite. The priest who had drawn his name called out for everyone to be quiet and to respect the ancestor, telling them about the old times and that this would just be another trial they would face.
He was certain that through the rite of initiation, either the man would find a child able to take his seed and make offspring to carry his likeness or he would not and end as a fluke of nature. In either case it was not for them to decide to change tradition the ancestor had decreed, but to let nature decide on what to do. 
The sobs of the childs live giver, his mother by blood, rang through the crowd as she ran off unwilling to bear witness to what was to come. Even if most pregnancies were just an everyday occurrence at this point, many females showed signs at that moment. Some mothers still held great feelings for their children and even hoped to be the ones to initiate their offspring.


Even if Tim felt a sudden spike of guilt about what he was about to do to the girl, this was an extremely rare opportunity for him. Regardless, with the rampant overpopulation taking place, he knew well that most people would find an excuse to tolerate what was about to happen. Behind closed doors the old ways, the priest had talked about, were still being practiced only with different tools. 
In truth Tim even once witnessed how his father and a group of his friends had taken a newborn to his fathers bedroom. Hearing many loud screams from the girls he knew something bad was happening, when she never came back out he knew she was likely fucked or tortured to death to keep population growth sustainable. Unbeknownst to him there have even been talks that night about using him to such an extent giving him time with the little one and maybe more.


Then finally it was time to continue, after some more talking and explaining the priest called on him to go up on stage and claim his prize. When Tim went up to the girl he had to hold himself back from rushing up and then finally he could see the naked infant laying on the altar. Standing so close to the girl he couldn't help but compare his own size to her. His dick was twice as long and almost as wide as the girl's torso.
While Tim was already fantasizing about what was about to come, the priest continued with the ceremony. While he wasn't listening this wasn't his first hearing it either so he knew the speech about the greatness of the ancestor and how they should live up to his image and do as he would and so on. So he only snapped out of his wet daydreams when the Priest put his hand on Tims shoulder to ask if he would like to perform the rite in public or prefer to do so in private.
While it was customary to do so in public or at least have the mother witness the act, the tone in which the priest asked him, was heavily suggesting to do so in private. Usually a witness or proof of the deed was required and he was about to ask, but the priest shook his head just for him to see, with an expression that told him that no one expected the girl to make it. 
Tim was considering doing it outside regardless, this was his triumphant moment after all. He badly wanted to be cheered on like the other times he witnessed, but considering what was most likely to happen, he didn't think the crowd would be on his side.


So in the end he picked up the tiny girl and started following the priest to the private initiation chamber. Through the relieved sighs of the crowd he thought he could hear some disappointed murmurs, but now he could enjoy his daughter by rite and sister by blood as much as he wanted regardless of the consequences. 
Even while walking he couldn't hold himself back and already began sliding his spit slickened fingers inside the girl's unused newborn pussy. The girl quickly began to tear up and squirm uncomfortably inside his arms, but he persisted and continued to force his first finger in deeper and even add another as he kept walking.
As they continued to walk his huge cock began leaking copious amounts of pre cum on the floor which left a noticeable trail behind him. He was so invested in fingering the girl's tiny hole and imagining what it must feel like to be inside of her, that he didn't even notice as she began crying and thrashing.
The priest walking in front of Tim was looking back every now and then seeming concerned as to what was about to happen. Tim was so engrossed with the newborn in his arms that he didn't notice, even as the priest made up an excuse to quickly leave the two of them alone, after they reached the initiation room.


Tim was already knuckle deep with three fingers into the girl at this point and even then it was only a tiny drop in a pond compared to what was sure to follow. Without any patience to begin with, he hurriedly threw the girl onto the bed, his fingers being roughly janked out of the girl. The newborn wasn't even able to process the change, before he was on top of her, his enormous cock oozing pre cum over her virgin pussy. 
While Tim had plenty of sexual experience forced upon him, most of that was his cock being used by his father as a sextoy, or his fathers friends getting to have their way with him. Unfortunately that lack of experience, combined with the youthful desire of a boy with a massive cock, would soon be detrimental for the newborn girl. Without any regard for the infant and driven by desire he rushed onward and already began prodding his massive throbbing cocktip against her tiny virgin entrance.
The girl had been continuously crying after he had carelessly thrown her on the bed, still recovering from the forceful stretching she endured before. After having a small moment of respite she quieted a bit, soon getting confused as to what was being done to her, as she felt the pressure from his massive shaft. However  even with his flood of pre cum drenching her and acting as lubrication, Tims attempt at penetration pushed her away rather than getting his cock inside of her.
Tim quickly grew annoyed at his failure, so he threw caution out of the window and grabbed her by the ankles, forcefully dragging her down against his massive dick. She immediately began to scream in pain once more, as the pain felt to her as if he was trying to tear her legs off. The newborn girl wasn't even able to understand that he was trying to force himself inside of her, which would certainly mean even worse pain for her.
The boy got more and more frustrated as regardless of how hard he pulled and pushed, he still seemed unable to get inside of her. He was about to give up as the force on his cock became painful even for him, when suddenly with a satisfying wet slurping noise the tip of his cock stretched her pussy out far enough and finally went inside.
To his great surprise, especially after he was about to give up, his prayers were answered. Even with his ginormous cock, taking the newborn's virginity, there didn't appear to be more blood than was expected for a girl's first time. However the deafening screams coming from the newborn were a clear indicator that it was not painless for the girl whatsoever.
Tim didn't care however as the pleasure of having his infant sisters cunny stretch around his ridiculous sized cock was overwhelming. Only the new knowledge that this might not be a one time thing as somehow his sister was able to take him, was holding him back from ravaging her completely at this point already. So with at least some care to not tear her apart, he began pushing his cock in deeper inside of her.
He marveled as he watched his dick stretch her out excessively, even his pulsing veins were clearly visible through her thinly stretched skin. If he weren't scared of just slipping out of her at this point, he might have dared to touch and pleasure himself while inside her. For now he just pulled her down further down his massive shaft, surprisingly getting inside seemed to have been the tough part. Even though her newborn pussy was extremely tight he was slipping in further easier then expected.
At this point he had phased out the deafening screams coming from his unwilling partner, only when she suddenly stopped he noticed something had changed. At first he grew concerned that his baby sister had been broken after all, but to his surprise she just seemed to have run out of energy screaming, no longer able to scream, or considering where his dick was, maybe she wasn't able to gather enough air. 
At this point he had managed to get around half his size inside of her, making her belly expand just over her face. He had to move his dick around to see the girl's face which still appeared awake and in pain. Confirming that she was indeed still alive was all the encouragement he needed to continue his incestuous actions.


From this point onward it got harder to push his huge cub meat further inside of her, but that didn't stop him from trying and succeeding in going past her cervix. He enjoyed the extreme tightness of her newborn flesh around his throbbing shaft and since he still didn't seem to cause any severe injuries he just kept going. At this point he started to have some trouble not blowing his load too early, having had no prior experience like this, he still managed to hold on until he forced himself completely inside of her. 
At that point the newborn girl was nothing more than a living condom for him to use. Her belly was now twice the size of her own torso and yet she was still holding together. It looked almost comical as every time his dick twitched, throbbing or moved in any form, the girl was shaken thoroughly. He even stopped to admire and play around for a little moment to increase his endurance as he was getting extremely close at that point.
The joy the young boy felt at that very moment was immeasurable, knowing his sister was born to take his cock and feeling her tightly clinging around it was soon proving too much. He hadn't even started thrusting for real, when his first orgasm came over him, regardless of him trying to take a small break. He could watch, as his massive load was shooting inside the girl and then inflated her belly like a balloon.
While he had expected something like this, his first load of the night was much more excessive than he could have ever dreamt of. He never considered that with this being his first time breeding a girl, his body was desperately trying to impregnate her, even if she was still a newborn, unlikely to get pregnant even with all the mutations going around. Each rope of hot cum he shot inside of her first pushed her belly out in front as the force was too extreme and then added to her rapidly growing belly.
Even if he would have tried to, there would have been nothing short of pulling out to stop his massive load from continuously flooding the abused tiny girl, which he sure as hell wouldn't do with how amazing it felt. The orgasm quickly left Tim too delirious to worry about her obscenely growing belly seemingly threatening to burst at any moment and yet still able to grow. 
When he was eventually done shooting his load inside of her, her belly had become big enough that he couldn't see any part of her anymore. Worried that she might be suffocated by her swollen belly, he quickly pulled out expecting a huge flood of cum to pour out of her, but was surprised as she quickly tightened back up, only a small stream flooding out of her.
Then he turned her over only to be surprised, seeing she was still alive and conscious, though only to her detriment it seemed, as the girl was still crying and screaming silently. Now that he had finally done what he had dreamt about for so long, the new calm made him aware of what he had done to her. And while he felt some guilt and shame about hurting her, he also knew that he would fuck the newborn in front him again many many more times, one more time even at this moment as his massive cock was still hard.