Big Sister (TG/AP)

Jack and Ryan were sitting in Jack’s bedroom, taking turns playing video games and complaining about Jack’s older sister being able to boss them around just because she was a few years older than they were. 

“When did your sister get so bossy?” Ryan asked as he cracked open a soda. 

“Rachel’s ego has been growing ever since my parents started letting her babysit. She thinks she runs the house now, but she’s barely old enough to drive.” Jack rolled his eyes as he heard his older sister giggling on the phone with her boyfriend. 

“Must be nice to be the oldest. Kinda wish I wasn’t the youngest in my family.”

“Yeah. I just wish my sister knew what it’s like to be the younger sibling.”

The air seemed to vibrate as the boys made their offhanded wishes. Ryan felt a chill run down his spine, his body beginning to tremble as changes began beneath his skin.

“Did you feel that?” Ryan asked his friend nervously. 

“Yeah, what was that?”

“No clue, but I’m feeling kinda…weird…” the boy trailed off as he noticed his fingernails beginning to grow. Thinking he was hallucinating, he stood up and walked to the bathroom to splash some water on his face. He suddenly felt dizzy, like the room was shrinking, and he could’ve sworn he was taller than Jack now. 

“You ok?” Jack asked his panicking friend. 

“Yeah, I’m just gonna go wash up. Feels like it got hotter in here.”

The growing boy locked the bathroom door behind him as he stared at himself in the mirror. Something was definitely happening to him, and he had no idea why. He leaned in to inspect his face, shocked to see light freckles appearing on his cheeks. To make things worse, he also noticed the roots of his hair turning a dark red…the same shade as Jack and his sister’s. He reached for his phone to call for help, but before he could unlock it, he hunched over in pain as the changes accelerated.

The boy braced himself against the sink and winced as his bones began to shift and pop, growing longer and wider by the second. His spine elongated with a sickening sound as his shoulders broadened, tearing his shirt at the seams and exposing his hardening midriff. His lengthening nails scraped across the countertop as his hips widened with a painful crack. He looked down in terror as his legs continued to push him upwards, growing thicker and longer at the same time. His prepubescent was squeezed by his growing thighs, causing him to groan in discomfort as his now undersized clothes tightened around his growing body. 

His massive hips swayed back and forth as he tried to shift his weight to relieve the growing pressure on his groin. Things only got worse as his ass began to inflate, swallowing up the tatters of his shorts as his buttcheeks grew into a lustful heart shape. He looked back at his new behind as his spine cracked inwards, leaving him with a feminine curve and a pair of dimples right above his new asset. He gripped the countertop and groaned as a sudden surge of power began to flow through him, his muscles tensing as each fiber increased in strength. His breathing grew heavy as his changing body took on years of athletic prowess in a matter of seconds. His muscles bulged beneath his silky new skin, accentuating his feminine curves as his mind raced to control his changing body. He barely noticed that he had grown taller than the doorframe. 

Suddenly, the energy flowing through him coalesced around his crotch. He grabbed his stomach and hunched over as he felt his organs slipping around inside him, preparing his body for what was about to happen. In a sudden burst of pleasure, Ryan moaned as his boyhood was enveloped by a tight new pussy. He twitched in shock and pleasure with each movement of his sexual inversion, his testes settling in as ovaries and beginning to pump estrogen through his body while the tip of his cock took it’s new place at the top of his new sex as his new clit. He rubbed a trembling hand over the alien organ between his legs and quivered at the mere touch. He tried to stifle a coo of pleasure as he poked a finger between his new folds, disturbed by his changing voice. 

“What’s…happening…to…me…” he whimpered as his voice grew deep and sultry. He looked at himself in the mirror, shocked to see his boyish head on top of the body of a giant woman. His clothes began to morph before his very eyes, the tattered threads reconnecting themselves as their colors began to lighten. His shorts tightened into a pink thong, hugging his new sex as it rode up his jiggling ass cheeks. What scared him the most, though, was his shirt reforming into a massive bra, one that looked even bigger than the ones he’d seen in his mom’s closet. 

“Oh, no, please, no…” he began to cry as he stared at the empty cups on his chest. To his dismay, they wouldn’t be empty for long. He thrust his chest forward as the energy moved up his midriff and behind his nipples. He felt his eyes welling up with tears as his nippes began to grow wide, hardening and protruding against the cold air. He watched helplessly as two massive mounds of flesh grew out of his chest, filling the bra perfectly as the massive weight hung off the terrified boy’s chest. He grabbed his new boobs nervously, moaning again at the alien pleasures that wracked his boyish brain. He looked down at his new chest, barely able to see past his new cleavage, as a tear dropped onto his massive breasts. 

He looked at the mirror, trying to take in his new body and everything that just happened, when he noticed his hair was now completely red. He leaned in as more subtle changes happened across his face. His skull cracked as its shape became older and feminine, his lips growing thicker while his nose shifted into a perfectly cute button shape. His eyes widened as they took on a deep brown, his eyelids moving down into a perpetually alluring visage. He shook his head in denial as his hair grew out, cascading down past his shoulders and taking on a feminine scent from years of maintenance. When he finally looked up again, he didn’t recognize himself in the mirror. Who was he?

A lightning bolt fired in his brain as he stared at his new self, searing new memories into his mind. He grabbed his head in a futile attempt to fight the final phase of his transformation, but there was nothing he could do to stop his neurons firing off as his synapses rewired themselves. Memories of his childhood playing games and riding bikes morphed into a childhood of playing with dolls and joining the volleyball team. He remembered going through puberty, growing insanely tall and curvy, and suddenly being the desire of all the boys in school. He remembered his…first…time. Groans of resistance turned into moans of pleasure as memories of being raptured by the hottest boys in school engrained themselves into his brain. His new sex grew damper by the second as a lifetime of how to use it sprouted in his mind. He remembered making boys eat him out, their tongues swirling between his folds as their breath warmed his inner thighs. He was so big and intimidating, yet so sexy and alluring that the boys in school would do anything for the chance to be with…her. 

Ryan wanted to scream as his old life felt more and more like a distant dream, but he could only moan as his new life seduced him. He was older, sexier, more powerful…his wish had come true. He was the boss now. He tried to think of his friend Jack, but the name and image of the young boy lived somewhere else in his mind now. Jack wasn’t his friend…Jack was her little brother. She was Ashley, Jack was her little brother, and Rachel was her little sister. She was the oldest of the siblings at 23 years old, and she was home from college now that the volleyball league was done for the season. She smiled at herself in the mirror as she admired her form, blissfully letting her old life as Ryan drift to the back of her mind. 

The new girl stepped out of the bathroom and walked back to her brother’s bedroom.

“Hey little bro, I’m having some friends over for a pool party tonight, so just stay in your room, okay? Don’t worry, I’ll tell Rachel the same thing. She’s not old enough to be hanging out with us yet.”

Jack looked back and was shocked to see the massive woman standing in his doorway. 

“Who- wha- where’s Ryan?” The boy stammered. 

“Ryan? Who’s that?” She said with a smirk. Jack looked around the room to find that all of the family photos had this girl in them. It seemed that Jack’s mind was taking a bit to catch up with the new reality, but as the girl walked away, he remembered the wishes the two boys had made before Ryan ran to the bathroom. He had no idea how or why, but he knew that Ryan had walked into the bathroom and that woman walked out. He picked up a family photo and stared silently, struggling to wrap his head around the fact that his best friend was now his older sister. At least Rachel wasn’t the oldest anymore. 

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