Brother: It cannot be helped, I will play with you! The game says ‘Share’ so it is not a solo game. So what am I supposed to do to play with you?”

He doesn't know what kind of app this is, but he’s sure it's some kind of co-op game where you share items and weapons to defeat enemies. Not knowing how to play, the brother easily agreed and responded by reading “do you agree to share?” tab that was displayed on the screen.

Brother: “Oh! Is there voice recognition? For the time being, I will click ‘agree’”

He pressed the button and handed the phone back to his sister. The brother wondered what the app could do, but the sister smiled with satisfaction as she grabbed the phone.

.Sister: “Look, I can see brother’s status since he pressed OK!”

The sister showed her brother the screen. It contained height, weight, age, and other personal information that only her brother could have known.

Brother: “Hey, hey! I only clicked the agree button, so why is my personal information coming up!? Maybe something's been hacked!?”

A chill went down the brother’s spine as he thought he got into something dangerous.

Sister: “It’s okay! Now, My brother can share his height with me!b34;”

Brother “What?”

He did not understand what she meant. Along with trying to figure out what his sister said, he was now ‘looking at the same level’ as his sister, who had been looking down on a moment ago. The brother had now sat down at all. Nor was the sister standing on a chair. They were standing on the same floor and the brother and sister were seeing eye to eye.

Sister: “First of all, I got to share a foot of my brother’s height, so me and my brother are the same height!”

Sister: height, 4 foot 11 inches

Brother: height, 5 foot

The heights of both of them were displayed on the phone.

Sister: “Ah! It’s not fair that my brother is one inch taller than me. I will take that one inch! Heeb34;”

Sister: Height, 5 foot

Brother Height, 4 foot 11 inches

In an instant, the sister was a little bigger than her brother. It was not a big difference since it was only an inch, as she said, I felt it as I had to look up a little to look into her eyes.

Brother: Why am I getting smaller? Why is my sister getting bigger?”

He didn’t understand the logic. Something supernatural happens and one’s mind goes blank trying to figure it out.

Sister: “Because you said that you would play with me, right,  big brother? That’s why I asked it share your heightb34;”

His sister said as if it was obvious what happened. If that is what happened, the app is the cause of his problem, then it should be possible for him to return to normal by using it. So, the brother tries to reach and snatch the phone from his sister but…

Sister: “Hey! I just started, I don’t want to go backa374;a281;If I want to prevent it from being taken, then I will … hmm, yes! Big brother will have to get smallera374;a281;”

His sister grew larger right in front of his eyes. The brother tried to reach for the phone in his sister’s hand but she held the phone at a height that he couldn’t reach no matter how much he tried to reach that height. The sister held the screen down so that values on the phone could be seen by the brother.

Sister: height, 6 foot

Brother: height, 3 foot 11 inches.

Brother: “This is impossible! I am swapping heights with my sister…”

Sister: “My little brother is so cutea374;b34; I’m so big now, I am the same height that my brother wasb34; But I got big in the body of a child…”

Brother: “Aren’t you big enough already? Please give it back!

The older brother looked up at his sister and gave his opinion, but she did not hear his words, her mind was occupied thinking about what to do next.

Sister: “My brother is an adult and he is only 3 foot 11 inchs, and I’m 7 years old at 6 feet, right? I wonder how big I will be when I grow upa374;? You're interested in that, right? big brother?”

Brother: “Don’t tell me...no, can you share height with the same reason as your height with the app?”

Sister: “ding ding ding! You’re going to help me grow upb34;”

Brother: “Hold on a moment!! No more of this, Please!!”

Sister: “Na374;ob34; Because I want to become an adult and be biggerb34;”

The brother’s plea was in vain as his sister had already finished the input.

Her short, childish legs gradually grew longer and fleshier as they became more sensual. Up until now, the sister could make a ring with her hands and encircle it around her thighs with her fingertips touching, but now that she was growing into a busty and curvy woman, no matter how hard she tried, her fingers would sink into her soft flesh and there was no way she could reach around them. Her butt had begun originally petite but her pelvis widened to the extent that it exceeded the width of her shoulders. She had grown a big, huge, maternal ass… like one that can easily deliver babies. Naturally, it didn’t just stick out to the sides but also to the back, it was unlikely that any amount of commercial skirts and pants would be able to wrap around her overly large buttocks.

Sister; “My ass is so big and softa374;! It’s like boobsb34;”

They were so soft that if one put their hand into them, the fingers would sink forever. The buttocks, which were so large and big that they jiggled and bounced when she walked around, were so superb that they almost could be called a second pair of tits. Her hair had grown so beautifully long that it went past her waist, and her face transformed into a mature woman with sensual appeal while retaining her cuteness. The best part was her breasts. Her two large melons, which were bigger than her head, weight could be felt just by  looking at them. Her huge boobs swayed with her every breath were forbidden fruit that you cannot take your eyes off once you see them.

Chapter 3

Sister: “heh hehb34; I’ve gotten so much bigger than momb34;”

Brother: “.....!!”

The older brother saw the growth of his overly attractive sister, and when he was too embarrassed to continue watching her growing body, he turned his gaze to the floor and couldn’t see the moment her clothes burst into pieces.

Sister: “Big brother, you can look upb34;”

Brother: “But your clothes are torn and scattered all over the place, right? If I look up now, I will see you naked as a grown woman…”

Sister: “I wore a very stretchy swimsuit underneath, just in case something like this happened, so it’s okay!”

Brother: “But…”

There were two reasons why the brother didn’t look up. One, because he didn’t want to accept the current reality, and two…

Sister: “Oh my gosha374;! You’re so insensitive! Look at this!”

The sister grabs her brother's head and forces him to look up. When that happens, even if he didn’t want to, his sister's body that had grown so large, jumps into view. This is the first time he’s ever seen such a thing.

Brother: “............!!!!!!”

The brother could no longer speak. No, he couldn’t. He had never seen a woman with such a beautiful and erotic body. The fact that it was his sister, almost blew his mind.

Br bu boing….

It was the brother’s that responded instead of his mouth, which could not speak. This was his second reason. This is because he thought that a brother should not lust after his sister.

Sister: “What do you think? I’ve gotten really big, haven’t I? I am 8 foot 3 inches tall now! Big brother…. He’s only 3 foot 3, isn’t he? You’re so tinyb34;”