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CYOTF (Human)

Big Bro, Bigger Sis

added by Wyndon 3 years ago AP BM S O

Jace layed in bed for most of the night. Thinking.
He knew that in the next few days his sister would keep growing. He was worrying that she would find out it was him. He would have betrayed her.
He knew he had to do something about it the best way he could.

He slid his bookshelf across the floor. With his new strength he could borderline pick it up all the way. He moved it in front of his bed, he saw the door.

He walked over and through the door, the Sundial was still there. It didn’t look too different, the only thing that had changed was the room. The vines and leaves that covered the windows seemed to have grown longer and thicker.
“Sundial?”
“Jace...” it whispered in his ear, still as eerie as before, “is there something ground desire?”
“Yes,” Jace said, “yes there is.”
“I can provide all that you need. Tell me what it is that you want,”
“I want my sister to be fine with all the changes. I want her to ignore them completely. Her changes my changes. I want her to think everything is normal.”
“Is that all you desire? Are you sure you want her to see you as a scrawny little pathetic boy, just another hormonal teenager?”
“Hey what the hell!” Jace yelled,
“But Jace, you are that no longer. You are strong, you are big in all the places where it matters, as you said. Why have her see you as her little brother, when you could be seen as her brother,”
“I... I mean,”
“Jace. I can sense you want this. And the price won’t affect you in any way, I promise,”
“Y-you... you promise?”
“Absolutely,”
“Then...”
“Yes, Jace?”
“Then I take the deal,”

Jace watched as the same thing as before happened, the Sundial glowed a faint blue, then stopped.
He waited for anything else. Nothing. Not a whisper to be heard or a light to be seen. He left the room and got himself into bed. He was satisfied with his choice. As he was falling asleep, he realised something. The sundial didn’t tell him the price.
He quickly sat upright, reading to ask the sundial. Then he fell asleep.



The next morning, Jace woke up, he was on the floor.
‘I must’ve rolled off my bed in my sleep. Weird,’ he thought to himself.
He looked at himself, his muscles looked around the same size as yesterday. He looked in the mirror. He flexed. Yep, pretty much the same.
He made his way up the ladder to find his sister making breakfast, she was, as usual, making bacon and eggs. He went to brush his teeth. He came out the bathroom and sat down, he completely forgot to look at her changes. So he looked at her. Since he’d grown, he’d had trouble adjusting to the new size of everything. He looked at his sister, she did look a little taller than yesterday. But before he could study her from behind any longer, she grabbed two plates of food and spun around.

As Blue spun around, and she literally did spin around on one foot. Her chest swung from one side to the other, juggling around, they were bigger than yesterday alright. Jace had to hold back being turned on, which he did succeed in doing. He looked at her chest. Yesterday they were pretty big. But today they must’ve been two thirds bigger. They were very big, and since she wasn’t wearing a bra they weren’t too supported. They were firm however, they were pretty full looking. Her nipples, compared to yesterday, they were twice the size. Her nipples were dark too, and pointy, they pointed far through her top. Below that, her belly looked a little paunchy. Her tank top hadn’t changed size, her breasts held it up, showing off her belly, which did clearly stick out over her waistline. The start of love handles has begun to appear too. Her hips were wider too. And her butt, if yesterday took up a good amount of space then it was nearly doubled today. As she sat down on the chair, her butt no longer fit on it. Her thighs were thicker than before too. Despite her wide hips, they always touched. Her calves were bigger too, as were her arms. But they looked more muscular than fat. As she looked at Jace, he saw her beginning to get a double chin. It wasn’t much but there was definitely something happening. Her nose looked a bit bigger too, as did her ears. And most notably, her lips. They were doubled in thickness.

“Uh... how are you feeling, Blue,”
“Normal,” she said, her voice a little mumble with her new lips, “how about you?”
“Yeah... I’m fine...”
“Cool,” she said, she took a mouthful of bacon, “why?” She asked,
“No... no reason,” she said, nervous, “you don’t think you look different... at all... right?”
“What?” She said, scratching her forehead, “pfft! No!” She said loudly, she snickered, “why would I look different. Is it my titties?” She said, this caught a Jace by surprise, she’d spoken about her breasts before but he never even considered her calling them ‘titties’ before, “I’ve have these babies since I was 17 and I wouldn’t trade them for the world. But y’know, if they did get bigger, Tyler would love them even more,” she grabbed them and fondled them a bit, her nipples for a little harder.
“Uh...” Jace said,
“What?” She said, she had a face full of bacon, “you’ve seen me do that before. You’ve seen me do much worse before,” she laughed, then burped.

Something was weird with her today, he couldn’t tell why. Maybe it was a little weird but he thinks he could deal with it. But she was talking nonsense. Jace hadn’t seen Blue even touch her nipples before, let alone doing ‘much worse’ to herself. His sister was virgin and he knew it. She wouldn’t have ever masterbated if it saved the Earth.

Jace laid in bed, thinking about how his sister was acting today. He just thought about it. He heard noise from upstairs. He poked his head through and looked, her door was slightly open. He was his sister doing exactly what he thought she’d never do.



The next day, Jace awoke. He looked in his mirror, he was the same. He gathered that his change was completely over. He flexed again. He was very satisfied with his changes, he was sexy and strong and hot.
He made his way upstairs, he looked and saw his sister wasn’t out of her room yet. He was probably just up early. He went to the bathroom and brushed his teeth. He took a shower, enjoying running his hands over his muscular body.

He went back into the kitchen, Blue still wasn’t there. He decided to check on her. He knocked on her door. No answer. He took a deep breath and prepared for the worst. He opened her door. It wasn’t locked. He looked in.
She was sleeping. Her bedsheets weren’t on her, he could see her. Her underwear was wet. He quickly closed the door.
He decided to look at the clock. It was 11:17. Blue was never up later than 9am. This was weird. Something was clearly off here. All this stuff. It didn’t match up to how she was normally.

He sat and watched TV to distract himself. It was 12:37. She still wasn’t up. This was really unlike her.
All of a sudden, as Jace was about to go to his room, he heard a door open. He looked behind the TV. Her door wasn’t open, instead he watched as a boy walked in. He had a backpack on, his hair was long and straight. He was wearing a blue t-shirt that looked old and worn and hadn’t been ironed in months. He had a goatee, he couldn’t have been older than 22. He looked a little older than Jace but that was just in the eyes, he was tiny compared to Jace.

“Hey, bud,” the boy said,
“Uh...” Jace said, confused, “hey?”
“You watching any porn on there?” He asked,
“What!?” Jace said, very loud, “no. Why would I do that with Blue in the house? Where she could see?”
“Huh?” The boy said, “so does she not watch porn anymore.”
“No! I mean... she never watched porn to begin with,”
“Uh... dude I remember walking in a seeing you two jerking off to an 80’s porn movie once,”
“What!? I don’t even watch porn... that much, and I definitely wasn’t watching anything like that right now. I wasn’t even watching anything sexy,”
“Tell that to your dick, dude,” he said, pointing at Jace’s pants. He was at a semi, his dick was poking out the bottom of his underwear, which was the only thing he was wearing other than that oversized, or rather normal sized, tank top,
“So where’s Blue,” he said, “I bought her something nice,”

Before anyone could say anything, Blue opened her door. She wiped her eyes,
“Tyler!!” She said, grabbing him by his shirt and wrapping her lips around his.

Jace looked at his sister, her body was different again, the first thing he noticed, her lips. They were bigger again. They could easily be mistaken for surgery. Her face was officially a double chin if she lent in the right angle. Her breasts were touching her boyfriends body and spilling over the side of him. Jace looked at her nipples, which had grown again, before Tyler grabbed them and began to squeeze them. Her legs were thicker, her ass was rounder and her hips were wider. Her feet was also bigger, she looked like she’d broken through her socks but didn’t care. Tyler’s cock was hard, it was touching her vagina under her underwear. Jace didn’t take note of his sisters vagina but it looked bigger, puffier than it had ever been.
Her belly, it spilled over her waistline. And all around it.

Jace spent the rest of the day avoiding them. He ignored them and just took this as his sister finally had a boyfriend and was happy. That’s all he cared about. He distracted himself for the rest of the day.



He awoke at 3:00am to a noise.
He looked around, it wasn’t anything in his room. He decided to peak his head upstairs. He stepped up his ladder. Then he saw it.

His sister and Tyler, on the couch. They were having sex. Real, hard, sex.
Jace had never seen two people have sex in person, let alone his sister and some weirdo.
He stood there, his jaw wide open.
“What the fuck!?” He said,
Tyler looked up and over to Jace, “hey bud, you wanna get in on me plowing your sister?” He asked, not joking, very seriously.
Jace looked at his sister. Her breasts were bigger. They were bigger than watermelons times two by now. Her butt was giant, her belly was huge too. Her her lips were thicker than her thumb each. Her nipples were as wide as the palm of her hand.
“What the FUCK!?”


What do you do now?


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