Hyper Virus Pt. 02

Story Info
A virus that causes growth for males and females.
2.9k words
4.22
17.4k
37
0

Part 2 of the 2 part series

Updated 09/08/2023
Created 08/11/2023
Share this Story

Font Size

Default Font Size

Font Spacing

Default Font Spacing

Font Face

Default Font Face

Reading Theme

Default Theme (White)
You need to Log In or Sign Up to have your customization saved in your Literotica profile.
PUBLIC BETA

Note: You can change font size, font face, and turn on dark mode by clicking the "A" icon tab in the Story Info Box.

You can temporarily switch back to a Classic Literotica® experience during our ongoing public Beta testing. Please consider leaving feedback on issues you experience or suggest improvements.

Click here

There was a knock at the door as Ethan was preparing dinner. Ethan walks over to open the door

"Hi Ethan" Caitlyn says.

Caitlyn was my slightly younger sister and looked similar to Mom with her facial features and brown hair, but she got her brown eyes from Dad. She was a bit shorter, standing around 5'3". Before the Quarantine she had already a large pair of breasts around H-Cup. After opening the door Ethan was surprised to find she had grown to a K-Cup.

"Can I come in?" Caitlyn asked

"Uh, yeah come in. Dinner is almost ready. How have you been?"

"Terrible. School sucks and my roommate cant stop bragging about her boyfriend and her O-Cup tits. Where is Mom?" She asked

"She wont be joining us for dinner, she is um, working late in her room. She said she will join us after dinner."

After finishing making dinner Ethan takes dinner to his Mother's room while Caitlyn sits at the table.

"Are you sure about this mom?" Ethan asked

"I'm sure. Knowing how I felt after catching the virus I'm sure she would jump at the chance if you offered. Have her come to see me after dinner. When she sees how big you made me, I have no doubt in my mind she will be all over you." She said as she reached to brush Ethan's hardening dick.

After going back to eat with Caitlyn. The siblings had casual conversation until...

"So did you get infected by the virus? I know Mom came over but I wasn't sure if she got it from me." Caitlyn said.

Ethan blushed.

"Yeah. Mom got it and a few days later I got it"

"Really? How big did her tits grow?" Caitlyn asked.

"Pretty big. You grew pretty big as well"

"Thanks bro. You like them?" She asked as she shook side to side

"I do. Your boobs are awesome"

Caitlyn smiled

"Thanks bro. I wish I had a boyfriend to pay attention to them."

Ethan blushed even harder.

"Do you not have a boyfriend?" Ethan asked

Caitlyn looked down and blushed.

"No. I dated a guy for a few weeks but we broke up before the virus."

"Do you miss him?" Ethan asked

Caitlyn blushed and shook her head yes.

"I don't have anyone to play with either." Ethan said

"Why not? You are pretty good looking, and a great guy"

"Thanks. I was too concentrated on school and work but it definitely has gotten lonely since quarantine started. But, if you need someone. I'm here"

Caitlyn blushed and looked away

"You're my brother. I cant let myself think that way about you. Plus, what would Mom say?" She said

"How about we go and see her?" Ethan said

As they entered Moms room. Mom was in her bed under the covers watching TV.

"Hi Caitlyn!" Mom said as she entered the room.

"Hey Mom. How are you?"

"I'm doing well! Your brother has been very helpful around the house."

Ethan, now sitting on Mom's bed, blushed.

"Ethan told me you got the Virus. How big did you get mom?" Caitlyn asked

Mom blushed "Well i grew to be about a J-Cup but after a fun night with your brother..." She pulled the covers off to reveal her massive mounds of tits, resting in her lap. "I love my tits, so big and soft!" Mom smooshed her tits together.

"Wow. You and Ethan... Did it?" Caitlyn said, blushing.

"I was in heat so yes, I fucked him. And then he made me into a goddess with these massive breasts. I have no complaints."

Caitlyn sat on the bed and started to touch Mom's tits.

"If you ask your brother, he would be more than happy to give you tits as big as these." Mom whispered.

"I.. I would like too..." Caitlyn said shyly.

Mom smiled and crawled to the edge of the bed where Ethan was sitting, and started undo his pants. She pulled out his hard foot and a half dick. Caitlyn was speechless at how big it was. She had seen a few dicks but Ethan was so much bigger than any of her past boyfriends.

"So big..." Caitlyn said.

Ethan blushed at how Caitlyn was looking at his cock.

"What do you think, should we make your tits grow? A big breasted goddess, just like me?" Mom said.

Caitlyn smiled and nodded her head yes. Mom leaned over and licked the tip of his cock. She then opened her mouth and took the head inside. Ethan sighed at the sensation of Mom's tongue and mouth. Caitlyn then saw Mom start to slowly deep throat Ethan's cock. Mom used her tits to pull Ethan down to where he was lying on his back. Caitlyn sat next to him and looked down at her brother's massive cock going in and out of Mom's mouth. She grabbed her boobs and started to massage them. Caitlyn leaned over and whispered to Ethan.

"I can't believe your so big. I bet it felt amazing to fuck Mom."

"It did." He replied.

"Would you mind showing me how you made Mom like this?" She asked.

Mom stopped sucking and looked at Caitlyn

"I lubed him up. Go for it." Mom said as she crawled off of Ethan's dick.

"Are you sure?" Ethan asked

"I've never been more ready" she replied as she took off her pants and panties.

She saw her pussy was shaven and already dripping with juices. She layed on top of Ethan as his cock grazed her pussy.

"Please" Caitlyn said, "I want this. Please fuck me!"

Ethan rubbed the head of his dick along her pussy lips, feeling her wetness. He felt her entrance and slowly started to enter her. Caitlyn moaned in pleasure at her brother's cock entering her. Once he got half way in he stopped.

"Don't worry. I'm just trying to go slow, it feels great inside you."

Caitlyn smiled.

Ethan slowly started to pick up speed, fucking her. Caitlyn grabbed her brother's hands and put them on her massive tits.

"Please play with my tits."

Ethan started to rub his sisters boobs, feeling her soft titflesh in his hands. He squeezed her nipples and rolled them around with his fingers. He leaned up and started to lick her nipples as they bounced in front of her. Caitlyn moaned in pleasure as she felt Ethan play with her massive chest. After fucking her for a few more minutes, Ethan felt himself getting close to cumming.

"Caitlyn, im going to cum. You ready?" He asked

"Yeah. Im ready"

Ethan let out a loud groan and started cumming inside her pussy. He shot three thick wads of cum into his sister's cunt. Slowly filling her up with his cum. He pulled out and Caitlyn watched as Ethan's cum started to ooze out of her pussy.

"Now for the fun part" Mom said as she was playing with her breasts

*Gurgle*

Caitlyn's stomach started to shrink back to normal as her tits began to grow. After about ten seconds they were already L-cups. Within the next few minutes she had grown to an O-Cup.

"They're huge" Caitlyn said as she grabbed them.

"Not as huge as mine, but they will grow again if you fuck your brother some more." Mom said

Caitlyn smiled and climbed on top of her brother. She started to grind her pussy against Ethan's dick as it started to get hard again. Mom grabbed her own tits and started to massage them as Caitlyn's pussy slid across Ethan's cock. Caitlyn leaned over the edge of the bed. Ethan got up and pointed his cock her pussy. After a few seconds he started to lower himself into her. After he got about half of his length he looked at the wonderful sight before him.

"Do you want to fuck her again?" Mom asked as she layed down next to them.

Ethan nodded his head. He started to thrust into his sister's cunt. Mom leaned over and started to kiss Caitlyn's nipples. Ethan continued to fuck his sister for another ten minutes until he came again. Caitlyn feeling her brother filling her up with his seed noticed he was getting even bigger while thrusting deep inside her.

"Oh my god. He is growing bigger!" Caitlyn said.

"Isnt your brother wonderful?" Mom said as she played with Caitlyn's boobs.

Ethan continued fucking his sister until she came again. He slowed down and started to get even bigger. His testicles grew again, now from softballs to small melons!

"Slam that baby batter into me! I want to grow! I want to dwarf my roommate in size!" Caitlyn cried out as she was being fucked

Ethan felt himself getting closer to cumming. Caitlyn started to get wetter as she got hornier. After another few minutes of fucking Caitlyn's cunt, Ethan groaned loudly and started to fill her with his seed again.

"Bigger, Bigger, BIGGER!" She cried out.

Caitlyn felt her pussy being stretched out as Ethan came until she looked 9 months pregnant.

"MAKE ME HUGE!" Caitlyn screamed

Ethan smiled he continued to fuck his sister until his balls were empty. Caitlyn had grown so much that she was being lifted off the bed by her stomach. Ethan pulled his now flaccid cock out of Caitlyn's cunt. Even flaccid his dick looked huge.

*GURGLE*

A rumble that shook the bed as Caitlyn's stomach began to shrink once more as her tits grew and an alarming rate. Ethan layed back and watched as his sister grew, in a matter of minutes, bigger than any measurable cup, bigger than your mother!

*CRACK!*

The legs of the bed gave out from the weight of Caitlyn's breasts. They were the size of bean bags. Caitlyn's breasts had also begun to lactate. Ethan and mom looked over at Caitlyn, she had passed out from extreme pleasure.

Ethan looked at his mother. "Did we over do it?"

Mom shook her head no. She crawled over to Ethan and started sucking on his dick. After a few minutes he could feel his balls filling once again with seed. After getting his dick hard again. Mom stopped sucking and stood up.

"I have decided. I want to be as big as your sister. I want to leak milk from my breasts like i did when i was pregnant. Your sister can have my room since it doesn't look like she is going anywhere. We are going go to the living room and you will fuck me until you empty your balls and. Make. Me. HUGE!"

Ethan follows his mother into the living room leaving Caitlyn to rest in the other room. Ethan with his now 2 foot monster and melon sized testicles following his mother who currently has breasts big enough to reach her knees. Mom pulls the ottoman away from the living room couch to lean over awaiting Ethan to empty his balls into her.

"Sink that python into me and fill me till you are shooting blanks. I want to grow bigger than your sister!" Mom said.

"I will mom."

Ethan walked over to her, grabbing her ass, and then slid into her waiting cunt. He fucked her as hard as he could, pushing his giant cock as far as he could. Her whole body trembled from his powerful thrusts. Ethan pushed his hips into her to fuck his cock deep inside her and let loose with a load of cum, filling her to the brim with his seed, his sperm was like molten lava. Mom's eyes rolled back in her head and she screamed.

"Fuck! I can't believe how hard you are cumming! Fill me with your young sperm and make me your whore!" Mom moaned, but Ethan did not stop.

He continued to fuck his cock into her, filling her womb. He turned her over on her side to face the couch, lifting her legs over his shoulders. He wanted to fuck her as deep as possible.

"That's it! I'm a slut now! I am a sex whore for your big cock!" Mom moaned.

Mom screamed as Ethan came inside her once more, letting her take all of his seed as it filled her womb and overflowed. He was pouring gallons of his sperm into her. His body trembled and then collapsed on top of his mother, pulling his cock from her with an audible sucking sound. They both breathed hard for a moment. His mother was now laying on her beach ball sized stomach filled with Ethan's seed. Mom turned around to look at her son, who was now covered in her juices. She licked them from his cock, and then smiled up at him.

"I knew I made a good decision to get the virus. You mad me huge, your sister massive and now I'm going to grow even bigger." Mom said with a grin.

Mom pulled him close, kissing him on the lips, "Thank you honey. Now fuck me in the ass as I grow!"

"Yes, mother."

Ethan spread her asscheeks and pushed his cock into her. Mom groaned, her cunt muscles spasming, and her whole body shaking. Mom had never been fucked in the ass before now. Ethan was the only person she had ever given it too. He pushed into her as deep as he could, burying himself inside her and then began fucking her ass as hard as he could.

"Oh fuck yes! Fuck my ass harder!" Mom moaned.

Mom was seeing stars now, her whole body shaking with his pounding thrusts. She could feel the pressure building inside her. Her whole body was trembling.

*GURGLE*

Her massive stomach began to shrink. Her already massive tits growing bigger by the second lifting her up as Ethan thrust deeper into her ass. She screamed. Her whole body was convulsing now. Her stomach had shrunk completely. Mom screamed as she came on his cock. The room filled with the sounds of her squirting juices as her whole body shook. Mom arched her back and pushed back hard onto his cock. Mom was still cumming as she felt Ethan's cock begin to twitch inside her ass.

"Yes! I want your sperm in my ass! Fuck me hard and cum in my ass!" Mom moaned as she continued to orgasm.

Ethan groaned, he began to shoot his massive load into her ass, filling it completely and then some. His huge cock swelled even more inside her. Mom moaned and came again, her whole body spasming as her breast grew to the size of bean bags. Mom pushed back onto his cock again as it began to grow larger. His cock was now 2 and a half feet long, as hard as iron and growing thicker.

"Yes! Give me your cock! Fuck me! Fill my ass with your young sperm and make me your whore!" Mom screamed.

Mom had been right about that. The virus did grow her and his sister big, but now her ass was filled with his seed and it was beginning to grow as well. Mom pushed back on his cock, grunting and moaning as her ass stretched even more to fit his giant cock. Her ass was now three times her original size, still growing. Her pussy was gushing, and juices ran from her pussy onto his melon sized balls, slapping into her pussy. Her legs began to quiver, her body trembled as she screamed out in ecstasy as her ass reached its limit. Her pussy was dripping. Her massive boobs slowing their growth, her nipples growing as long as fingers, becoming almost as thick as soda cans. Mom passing out from pure bliss. Taking his cock out, Ethan finding the couch, passed out as well.

Mom and Ethan both woke up, realizing that they had slept through the morning and most of the afternoon. The room was filled with Mom's massive boobs in a puddle of white liquid.

"Looks like I've been leaking milk" Mom said with a smile. "You were so good to me."

Mom was huge, her stomach had shrunk completely. Her boobs were now each the size of a large bean bag with milk running down them in thick streams. Her ass had grown so much, it jiggled with each movement she made.

"Well I need to check on Caitlyn." Ethan said. "I'll come back with a blanket and some towels for you"

"Thank you honey." Mom replied.

Ethan walked over to his now sister's room and pushed open her door. She was lying on her breasts in the middle of the room.

"Caitlyn? You awake?" Ethan said.

Caitlyn was watching the news. "Come in they are making an announcement about the virus"

"The scientists responsible for the virus have been busy with trying to make a cure. A cure has not been found but we now have means to reverse the growth effects from the virus. This will not prevent you from growing again, but can reverse any unwanted growth and can be readministered if growth occurs again. We...."

"You know what this means Ethan? We can do this over and over again as much as we want. You can make us as big as you want and we can make you as big as we want." Caitlyn said, grinning at him.

"Well that opens up some possibilities as I was able to make mom's ass grow last night after you passed out" Ethan said.

"You what?"

"I fucked her ass as it grew bigger. She really enjoyed it"

"Well it cant hurt to have a little more junk in the trunk" Caitlyn said

The End?

Please rate this story
The author would appreciate your feedback.
  • COMMENTS
Anonymous
Our Comments Policy is available in the Lit FAQ
Post as:
Anonymous
Share this Story

READ MORE OF THIS SERIES

Hyper Virus Previous Part
Hyper Virus Series Info

Similar Stories

Accidental Size Effects Ch. 01 Pills have some unexpected side effects. Mom needs to help.in Incest/Taboo
Growth Spurt Pt. 01 A drug trial changes Jimmy's life forever.in Incest/Taboo
Mom To The Rescue Pt. 01 Virgin with Huge Cock needs to get laid.in First Time
Accidents Happen! A brother and sister make a discovery.in Incest/Taboo
It Just Sorta Happened big sis, lil bro, tickle fight, accidental creampie(s)in Incest/Taboo
More Stories