Ch. 01: An Unfortunate Discovery!

Nagareboshi Hikari Ch. 01: An Unfortunate Discovery!

By Kaisai (kaisai134)

Story contains female muscle growth and breast expansion

Hikari Hoshino is an average 1^st year high school girl at Tsubasaumi High School, an average high school, in an average bayside town located somewhere close to Tokyo, Japan.

*Trope Alarm is blaring like crazy*

…shut up…

She is 16 years old, stands around 165 cm tall, has an average C cup bust, long, brown hair that stops in the middle of her back, hazel eyes, average build. She wears red half-rimmed glasses to correct nearsightedness, has a pink heart hairpin in her hair, and is currently in her school’s orange and blue seifuku uniform with gray kneesocks and plain brown shoes. Hikari is on her way to school, walking up the hill in which it sits upon.

“Hey Hikari!” A voice calls out.

Hikari turns around to see the source of the voice. She spots a familiar girl running up the hill towards her.

“Oh, hi Miya-san! How are you doing today?” Hikari waves.

Miya Taguchi is one of Hikari’s two friends. She is somewhat of a stunner who attracts attention of all the boys in the school. She is around the same height as Hikari but has a much more prominent bust. She has short black hair, brown eyes and wears a big white ribbon in her hair.

“Running late as usual!!” Miya shouts in between breaths.

“Well, that can be solved easily. You just need to start getting up on time.” Hikari giggles.

Miya catches up to her.

“It’s not my fault that they were running a cool special on UFO’s last night until 2 in the morning!” Miya whines.

“Yeah, well I seriously doubt they run the same special every night Miya!” A voice calls out beside Hikari.

The girl who just appeared beside the two of them is Keiko Okada. She is a few centimeters shorter than the other two girls. She has an athletic build, which shows her dedication to being a track athlete. Short cropped blue hair with a white hairband, blue eyes, and smaller than the other two in the bust department.

“Oh be quiet Keiko!” Miya shouts. “I haven’t been late for school once!”

“Well, there was that time when you came really close and had to jump over the gate…” Hikari says.

“But I still wasn’t late!”

Hikari laughs, Keiko steams.

“Just start going to bed earlier damnit!!”

All three of them walk in through the gate to the school. They split up and go to their classes, Keiko is in a separate class from the other two. Morning classes go as usual and lunchtime arrives. Hikari pulls out a nicely done bento box she made herself, Miya pulls out a bag of melonpan and curry pan.

“Miya-san, is that all you are going to eat?” Hikari asks opening her bento.

“This is all I could grab running out of the house this morning.” Miya replies.

“Would you like some of mine?”

“Sure! Oh wait…”

“What is it?”

A conversation between two guys can be heard at the front of the room.

“Looks like Ikuto forgot his to… Now’s your chance Hikari!” Miya says.

“Wha… what do you mean?” Hikari replies.

“Go offer him your bento!”

“Why should I do… do that?!”

“Aren’t you attracted to him? Go on ahead and do it!”

“O… Okay….” Hikari replies blushing as she covers it up and walks up to him.

Ikuto Hirono is sitting at his desk hungry. He’s around 170 cm tall, skinny, short, choppy brown hair and brown eyes. He notices as Hikari walks up to him.

“Oh, hi Hoshino-san. What is it that you want?” He asks.

“I… I heard you f… forgot your lunch. Wo… would you like s… some of mine?” Hikari asks him blushing and swaying about.

She holds out her bento.

“Awesome!! I would love to have some! Thanks a lot Hoshino-san, you saved my life!” He shouts. “Go ahead and pull up a seat.”

Hikari looks back at Miya. Miya gives her a thumbs up as she takes a big bite of the curry pan. Hikari pulls up a seat and sits at Ikuto’s desk. She opens up the bento and hands him a pair of chopsticks. Ikuto takes a bite of the omelet.

“This is amazing! Did you make this all yourself?” Ikuto asks while sampling everything.

“Y… yes.” Hikari replies while eating.

“I would love it if a cute girl like you would make me a bento like this every day!”

“Really?!”

“Yes really!”

“Okay… so what kind of food do you like?”

Ikuto rattles off a list of his favorite foods while Hikari takes notes. After they both finish the bento, Ikuto thanks Hikari and she returns to her seat beaming.

“So?” Miya asks.

“He wants me to start making bentos for him each day.”

“And…”

“I got a list of his favorite foods… thank you Miya-san!!”

“No problem!”

“Today must be my lucky day!” Hikari says excitedly.

Next period was biology. They are studying about the relationships between organisms.

“And next are the parasites. A parasitic relationship between two organisms is where one organism harms the other in order to survive. Here is an example of parasitic wasps that use caterpillars as their hosts…. And next, various parasitic worms inhabit animals such as hookworms, roundworms, tapeworms…”

Hikari is squirming in her seat at the sights the teacher is showing of the different parasites. She turns her head to avoid looking at the screen. She is greeted face-to-face with a spider that started descending from the ceiling.

“KYAAAAAAA!!!!!!” Hikari screams as she jumps out of her seat and backs away. The spider drops to the ground and begins scurrying.

Everyone in the class looks at Hikari. Miya stands up and steps on the spider, then sits back down. Hikari looks around at everyone staring at her. She sits back down as well. Class then resumes.

“… some parasites are able to control their hosts central nervous system in order to make spreading easier or make the environment more hospitable for the parasite…”

“All that over a little spider?” Miya whispers.

“It wasn’t little! It was right in my face!” Hikari whispers back.

“Whatever scaredy cat.”

After school, Hikari and Miya meet back up with Keiko.

“Hey Keiko!” Miya calls out. “Wanna go with us to the café? We’re celebrating Hikari-chan’s first step in making Ikuto her boyfriend!”

“Okay. Congrats Hikari!” Keiko says smacking Hikari on the back.

“Owww… Not so hard Keiko-san!” Hikari whines.

“Haha. Sorry! I’m so used to getting slapped on the back by the guys on the track team I forgot you’re a dainty girl!”

“I wouldn’t say she’s dainty there Keiko.” Miya says as she points to Hikari’s breasts. “Compared to you, she’s a model!”

Keiko reached around Hikari and jabbed Miya in the side.

Just as that happened, a light streamed across the sky towards the park and forest.

“What was that?!” Hikari shouted.

“I… I don’t know.” Keiko responds.

The three girls look around to see if anyone else saw the light.

“It’s strange, no one else is looking.” Hikari mentions.

“LET’S GO CHECK IT OUT!!” Shouts Miya.

“WHAT?!” Hikari and Keiko scream in unison.

“I bet it was a UFO!! Let’s go find it and see!! Let’s head towards the park!!”

“I don’t know about that Miya.”

“How… how about we don’t and say we did?” Hikari asks.

“Nonsense!” Miya shouts as she grabs both their hands!

“Hey!! Miya!! Wait!! We didn’t agree to go with you dumbass!!!” Keiko shouts.

“Please!! Let me go!! I don’t want to go!!” Hikari cries.

Miya drags the both of them with her.

Miya was right, it was a UFO. The spaceship has crashed just outside the perimeter of the park. A hole can be seen in the side of the side of the ship. Out of the hole can be seen crawling out are a bunch of neon green worm-like creatures the size of earthworms. They move in every direction, spreading out, searching for a host.

It was dusk when the three girls arrived at the wreck.

“Wow… look at it.” Miya says.

“I…I’ve never seen anything like it before.” Keiko comments.

“Okay… we’ve seen it. Now, let’s go back and let someone else deal with this.” Hikari trembles.

“I’m going in! Are you two with me?!” Miya asks.

“I’m game. My curiosity has been piqued.” Keiko replies.

“Yyyyyou tttwo can just ggggo right on aaaaahead. I’m just going to ststststand over hehehere.” Hikari works out while shaking.

“No! You’re coming with us!” Miya says as she grabs Hikari’s arm.

“If I’m doing this, you’re doing it to Hikari!!” Keiko says as she grabs Hikari’s other arm.

The two girls begin pulling her behind them.

“Noooo!!! Let me go!!! I don’t want to go inside the creepy spaceship!!!” Hikari whines.

“Quit yer damn whining and come on!!” Keiko shouts.

“C’mon Starlight-chan!! It’ll be fun!!” Miya adds.

“My name is Hikari!!! Not Starlight!!” Hikari continues to whine.

“Sure it is! Hoshino Hikari. Hoshi no Hikari!! Light of the stars! Starlight!” Miya quips as they get closer to the spaceship.

“Please!! Just let me go!!!!”

As this is going on, about 100 meters away, one of the worms has found a cute little mouse. The mouse scampers over to the worm. It begins sniffing the worm. The worm burrows into the mouse’s skin. The mouse flails around in pain. The worm disappears inside and the mouse starts glowing green. Its eyes becomes red. The small creature begins growing larger, and larger until it is the size of a small cat. Its teeth gets sharper and sharper as fangs start to appear. The fur becomes more and more disheveled giving a more feral appearance. Muscles begin popping up all over the creature. The tail splits into two as the creature roars and starts consuming everything in the area.

The three girls enters the ship from the hole in the side. Lights of various colors can be seen along the walls flashing. A central computer console can be seen across from what appears is the flight chair. A large humanoid body can be seen slumped forward in it. It appears to be dead. Sparks can be seen from various items within with lights flickering. A large glass tube can be seen off in the corner has been shattered during the crash.

“Wow…” Miya says awestruck.

“This… This is amazing.” Keiko says aloud in awe.

“I would say. Look at all of the pretty colors that are dancing around the walls…. Now can we please leave?!” Hikari says aloud.

“In just a minute scaredy cat!” Miya says aloud.

“Yeah Starlight, let’s explore just a little more.” Keiko adds.

“Now you’re going to start doing that Keiko-san?!”

Miya laughs as she walks up to the computer. She sees a bright red button that is flashing.

“I wonder what this does.”

“Don’t press it!!!” Hikari shouts.

“Oh but you know I have to press it!” Miya replies as she pushes the button.

Every light on the computer comes on and begins flashing wildly. Miya runs and stands back again beside Hikari and Keiko. Miya and Keiko are both sweatdropping, Hikari is starting to tremble in fear.

“OH NO!!! THIS IS BAD!! BAD BAD BAD!!” A young girl’s voice rings out from around them.

A light appears around all three girls. They start looking around for the source of the light.

“YOU!! EARTH GIRLS!!!” The voice shouts out.

“L…LET’S GET THE HELL OUT OF HERE!!!” Keiko shouts.

All three start to run. Hikari trips over her feet and falls hard onto the ground.

“WAIT!! MIYA-SAN!!! KEIKO-SAN!!! COME BACK!!!!!” Hikari cries out towards them. The two have already exited the ship still running.

A hologram of a cute young girl with light green hair and bright blue eyes appears in front of Hikari.

“AAHH!!” She screams and leans back.

“You!! You must help me!! The bioparasites have escaped and we must stop them!” The girl says.

“B…Biop…parasites?!” Hikari repeats with tears in her eyes backing up slowly.

“Yes! Bioparasites! Once they find a host, they cause the host to enlarge in size and begin consuming every living thing in sight to continue growing! We must stop them! And you, you are the most compatible!” The girl walks closer.

“C… Compatible…. Fo.. for what?!”

“The power armor to fight against the bioparasites! Though, we will need to optimize your body in order to fight them… never done it on a human before…”

“FIGHT!?! I… I DON’T WANT TO FIGHT!!!” Hikari cries.

“But you must! Or your planet is doomed!!

Hikari stands up and continues to stare at the hologram.

The hologram floats up to Hikari’s eye level.

“Do you want everyone on this planet to die?!”

“N…. no…” Hikari replies meekly.

“Then!!”

A black choker materializes around Hikari’s neck. It has a purple plate on the front of it with a light purple star in the center. Hikari grabs her neck and looks down. She starts patting it wildly and grabbing at the choker.

“N.. n… NO!! TAKE THIS OFF OF ME!!!” Hikari shouts as she cries.

“And now…”

Hikari starts running crying towards the hole where they entered.

“Let’s begin the optimization!!”

“KYAAAAAA!!!!!!” Hikari screams as she runs.

Hikari is caught in a bright beam of light before she makes it to the hole.

When Hikari opens her eyes, she sees an array of different colors surrounding her. Her body is glowing white like the light that surrounded her. She watches as her school uniform is replaced with a black, skin tight bodysuit that covers her torso and trunk, leaving her arms open. The suit leaves nothing to the imagination.

“What…What’s going on?!?” Hikari cries.

“Optimization: START!!” The hologram calls out. “First! Body!”

Hikari feels a strange energy flowing through her. She watches as her body begins pulsating all over. All of the sudden, she begins gaining definition all over her body as her muscles are starting to grow.

“Wha… WHAT ARE YOU DOING TO ME?!”

“Increasing your muscle mass, strength, flexibility, bone density, yada, yada.”

Hikari watches as she starts growing in height as well. Slowly growing in size from her 165 cm height. Her breasts are also beginning to expand within the suit.

“No…No.. NO STOP THIS!!!! PLEASE!!! STOP!!!” Hikari whines.

“Too late!!”

Hikari’s arms swell up with layers upon layers of muscle, her pectorals grow larger and larger pushing her still expanding breasts out. Her abdomen becomes tighter and tighter, with cobblestones of abdominal muscles swelling like rolls for a perfect six pack. Her quads and calves pulsate and grow, filling with more strength every time. Her shoulders have broadened to support her new found mass, and to give room for her back muscles to expand and grow. Her glutes have swollen and hardened into perfect hard hemispheres. When her body finishes growing, she is now 180 cm in height, well-muscled with F cup breasts.

“Next! Neurological!!! Eyesight, hearing, reflexes, yada yada ”

“Neuro what?!” Hikari cries and then she goes silent as she feels all of her nerves firing at once.

“PLEASE!!I BEG YOU!! STOP THIS!!! I DON’T WANT TO FIGHT!!!”

“Oh!!! You are starting to get on my nerves now!! Begin next phases concurrently! Mental and Cosmetic!!!”

Hikari continues whining and then stops immediately. Her hazel eyes widen and the pupils disappear, glassing over. Her eyes and hair change color to light pink and light lavender respectively. Her pink eyes begin to clarify, revealing her pupils again. Hikari blinks her eyes a few times and then gives a big smirk and raises her right arm and flexes her lemon-sized bicep.

“Ai-chan… I’m ready for the last phase!” Hikari shouts out.

“YAY!! Last but certainly not least… ARMOR!!!”

Hikari straightens out her arms as purple haloes of light start glowing around her head, arms, chest, waist, calves, and feet. On her arms materialize black gloves with purple piping that stop midway up her forearm. Around her chest forms a purple chest plate that conforms to the shape of her breasts, leaving them open at the top. Around her waist materializes a purple waist plate that also conforms to the shape of her body. Down at the calves and feet materializes a pair of purple and black metallic boots. And last, on her head materializes a pair of purple visor goggles that has various information streaming across them from the computer.

When the light around her disappears, Hikari is now standing there smiling. She puts her hands on her hips and turns towards the floating hologram. Hikari’s muscles can be seen through her body suit. They look like they belong on a professional athlete. She jumps around and does a few flips in the air, and handstands testing out her new body.

“This is amazing Ai-chan! I have never felt anything like this before.” Hikari says after doing five backflips and a perfect landing. She is still standing there now examining each muscle of her body, and her larger breasts.

“Ai-chan? Who is that?” The hologram asks.

“Why you, Ai-chan.. A.I.-chan.” Hikari replies as she flips the visor up on top of her head.

“OH!! OKAY!! I like that name! Ai-chan!!” Ai-chan squees.

“Hahaha. I figured you would.”

Hikari hears screams off in the distance.

“Did you hear that just now Ai-chan?!”

“Oh no!! They must have found a host already!! Hikari! You need to fight against the bioparasites in their host! As soon as the host has taken enough hits and damage, the parasite will emerge from the host. Then, you have to shoot it!” Ai-chan instructs.

“Shoot it? But I don’t have any…”

Two space-age looking purple guns materialize into her hands.

“guns…”

“All you have to do is think about them and they materialize!”

“And what if I need your help?”

Ai-chan disappears.

“I’m always going to be with you!”

Her hologram appears out of the star around Hikari’s neck.

“Thanks a bunch Ai-chan.”

“No problem Hikari!! Now, LET’S GO STOP THOSE BIOPARASITES!!”

“Right!”

Hikari runs out of the ship and starts leaping around towards the source of the scream.

Miya and Keiko are both cornered by the monstrous mouse. It has grown now to the size of a lion and the tail has split in three. Keiko is brandishing a sharp tree branch.

“Stay away from us you monster!!!” Keiko shouts.

The monster just roars at Keiko and bares its sharp fangs dripping in saliva.

“Keiko-san!! Miya-san!!! There you two are!!” A familiar voice calls out.

“Hikari-chan?! Is that you?! GET HELP!!!” Miya cries out.

“Don’t worry! Help is on the way!” The voice says as it grows closer.

Keiko and Miya watch as a tall figure lands behind the monster and grabs it by the tail tossing it aside as if it was nothing. They both stare at the womanly, muscled figure before them. She looks strangely familiar.

“Who… who are you?” Keiko works out.

Hikari grins.

“Like the light of the stars, I streak across the sky to where ever I may be needed in order to protect this world! I am…” Hikari poses after flipping up her visor on her head. “Nagareboshi Hikari!”

“Nagareboshi Hika… HIKARI-CHAN!?!”Miya shouts.

“Hi Miya-san and Keiko-san!”

“Hikari?! What in the hell happened to you!?” Keiko screams.

“Oh, just a few things… chosen to save the world… transformed into a superheroine… that kind of thing.” Hikari replies.

The monster mouse roars again and rushes towards Hikari.

“Oops! No time to talk right now…” Hikari says as she spins around and catches the jaws of the beast. “RUN!!!”

Keiko and Miya both make a run for it.

Hikari’s visor drops back down over her eyes as a health bar appears surrounding the beast.

“Alright now... Let’s do this!!” Hikari shouts as she flips back and materializes her guns.

Hikari fires a few shots at the beast. They hit and it roars in pain. She watches as the bar starts decreasing.

Hikari rushes up in front of the monster and jump kicks it in the side repeatedly. It continues to howl in pain. The monster raises up a leg and scratches her.

“AUGH!” Hikari jumps back and examines her arm that got scratched. It heals right up immediately as if nothing had happened.

“Accelerated healing… nice touch there Ai-chan!”

The monster starts charging again and jumps.

“Whoops…”

Hikari dives out of the way as the monster crashes where she was standing. She watches as the health bar continues to decrease faster.

“Not real smart doing that were you?”

Hikari punches the monster in the side hard 10 times and then jumps in the air and lands a dropkick on the monster’s spine. The monster howls more in pain and starts convulsing. Hikari jumps back a few meters away and looks on her visor seeing the bar in the red. From the back of the monster emerges a giant, neon green hydra-like creature flailing about.

“That must be the bioparasite!” Hikari shouts.

“Yes!! That is it! That’s a mature parasite!! Quickly! Shoot it!!” Ai-chan shouts with the choker blinking as she talks.

Hikari brandishes her guns and takes aim at the parasite flailing about. She fires rapidly at the creature. The creature starts disintegrating as more of its body is destroyed by the shots. After the last piece of the parasite disintegrates, the mouse begins to shrink back down to normal, severely wounded.

“YOU DID IT HIKARI!!!”

Hikari walks over and looks at the mouse.

“That is what that was… a single little mouse?”

“Yes. That is how horrible the bioparasites are. And there are more of them out there!”

Hikari dematerializes her guns.

“Well, rest assured Ai-chan, I am not going to just run away from this. I can’t let these parasites go around infecting everything they find and turning them into monsters.”

“Heh heh heh heh… sure Hikari… ‘I wonder if her real personality is going to agree with her…’”

Hikari leaps off after finding where Miya and Keiko are. She lands in front of them and flips her visor over her head.

“Hi there Miya-san and Keiko-san! I got rid of the monster for you. Though, there may be more out there.” Hikari warns.

“Thanks Hikari!!” Keiko shouts.

“Thanks a lot Nagareboshi Hikari-chan!” Miya shouts out as well. “So, are you stuck like that forever or can you transform?!”

“I can transform of course!” Hikari answers as she touches the star on her choker and begins glowing. “Until next time I am needed, Nagareboshi Hikari out!”

When the light has faded, Hikari has transformed out of her powered up battle armor form back to normal…

*creaaaakkk*

Or… maybe…

Keiko and Miya both stare agape at Hikari’s form.

“Keiko-san!! Miya-san!!! Oh thank goodness you are alive!! Why did you leave me back there?! Some computer said I had to fight scary monsters!! And it started causing me to grow! And and.. and..” Hikari says with tears in her eyes, crying.

“Umm… Hikari-chan…”

“What is it Miya-san?! And… why do my clothes feel tight?” Hikari asks still sobbing.

Keiko pulls out a mirror from her bag and holds it in front of Hikari.

Hikari looks in the mirror. She is still the 180 cm, F cup, muscled powerhouse. Her school uniform is stretched out over her new form. Her top has risen up to her breasts barring her midriff. Her sleeves are tight against her arms, with the cuff wrapped around her biceps. Her skirt has also risen up just below her crotch, and is lifted up slightly in the back from her glutes. The most shocking change is her eyes and hair. Her left eye has changed to the pink of her transformed state and her hair has become a gradient mix of her natural brown and the light lavender of her powered form.

“WHAT HAPPENED TO ME!?!?” Hikari cries out in tears.

“Yeeeeaaaah… Sorry about that Hikari. Remember, I said I’ve never optimized a human before…” Ai-chan’s hologram appears out of the choker.

“So… you mean…” Hikari sobs.

“You’re kinda stuck like that. But hey! Just think! You right now are one of the strongest people on Earth!” Ai-chan says cheerfully.

Hikari drops to her knees and cries harder.

“BUT I DON’T WANT TO BE ONE OF THE STRONGEST PEOPLE ON EARTH!!!”

“Hey Hikari-chan! Just think, you’ll be able to outdo Keiko-chan in everything now!”

“What was that Miya?!”

Hikari continues to whine. She stops and looks back at Ai-chan.

“So… I… have to fight those… bioparasite things?”

“Yep!”

Hikari grimaces and then throws her head back in the air.

“THIS IS THE MOST UNLUCKY DAY EVER!!!!” Hikari shouts into the sky as birds in the trees fly off.