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The day started like any other.
Senku rised with the sun, stretching his arms above his head, his body lean and healthy. Well, as healthy as one sleep deprived caffeine addicted teenager can get.
He rubs his tired eyes as he makes his way down stairs, careful not to wake his old man who came home late last night. The poor guy hasn’t been home for almost a week since he went away on a mandatory business trip with the rest of the astronauts he’s become easy friends with.
Senku pours himself a plain coffee, letting the caffeine wake him up. He looked outside for the daily newspaper that shows up at exactly 6:34 am on the dot by the same pimply faced teenager who looks like he just got out of bed and would rather walk into oncoming traffic then deliver papers at this hour.
When he opened the front door, no newspaper to be seen. Maybe the paper boy called in sick today, nothing unusual. But the scenery seemed weirdly different, Senku thought as he closed the door behind him.
Senku went back to his coffee, taking another sip. He looked down at the cup, he’s never seen it before. The chances of never seeing this cup before in his own household would be extremely low since this is a place of coffee addicts. Senku lifts it higher and reads the gold letters on the side. “Princess” it reads.
Senku suddenly gets an irritating ring in his ear, as he normally does he goes to pick at it. Finding his nails have somehow grown overnight and have gotten…manicured?
He recognizes those designs on the nails.
It couldn’t be.
No.
No!
Senku sets the cups down and rushes back up the stairs, taking notice to portraits he doesn’t recognize pinned to the walls. Each one looking plain and pristine, every smile and head tilt calculated.
He rushed past them all and opened every door trying to find the bathroom. Once he found it he stepped in front of the mirror and confirmed his greatest fear.
Dark blue eyes staring back him, the face of his classmate Asagiri Gwen wearing the panicked expression he felt.
He slowly and hesitantly brought a hand to his face, not wishing it to be true.
Senku felt and watched as the soft skin was being pulled and pushed under his manicured finger.
This was a dream. It had to be.
Senku, delirious, walked back to bed on trembling feet. Crawling under the covers and hoped that when he woke up he would be back in his own body, in his own home and that this was all just a dream he would surely wake up from.
A call coming from his phone crushed all those hopes.
He looked at the caller ID as it rung a catchy tune from a song Gwen probably like. “Senku <3” was in big bold letters on the screen. He groaned before picking up the phone, hitting call. “Hello?”
“Senkuuuu! Please tell me what’s going on!” Gwen squealed into the phone, it felt off putting hearing his own voice so high pitched and girly.
“How the hell would I know?”
“Well you’re the smartest person I know! I figured if anyone had an answer it would be you!” It was clear Gwen was on the verge of a breakdown and was barely keeping it together.
Senku groaned. “Meet me at school, and we’ll figure something out.” Senku was about to hang up before he remembered something. “And please…try to act normal.”
“Huh? What are you insinuating, Senku-chan? I am the epitome of ‘normal’” Gwen said dramatically through the phone.
“That’s exactly what I’m talking about. I don’t sound like that and I don’t talk like that. You need to act like me if we want to avoid suspicion.” Senku hoped this girl could act, otherwise his reputation will surely be ruined by the end of the day. “See you at school.”
He hung up the phone, turning over and groaning his frustration out into a pillow. He looked at the phone in his hand, he had an hour to get to school, might as well get ready.
Only when he went to undress did it finally click he was in girls body.
The bodily components he was so used to weren’t there anymore. His chest felt heavier and it was clear there was nothing between his legs anymore.
Senku went and stood in front of the mirror in the room, looking at himself from head to toe. Taking note of the wider hips and chest, thin pale arms at his sides.
He understood the female anatomy enough but being in one was a totally different experience.
Senku decided he spent enough time dawdling around and got dressed. Sifting through the closet to find a clean set of the girls uniform, stripping down and quickly getting dressed. It took him a while to fasten the bra on properly, not being too flexible to reach behind his back he decided to fasten it in the front before shifting it around to the back.
Senku went back downstairs downed the cold coffee he abandoned on the counter and ate a quick breakfast before texting Gwen again.
“I’m heading out now. Is there anything I need to know about before leaving?”
Gwen’s reply was almost immediate.
“If you’re asking if it’s that time of the month then no. You’re in the clear.”
Senku exhaled in relief, he really didn’t want to get a hands on experience of the menstrual cycle.
And with that all sorted out Senku left through the front door and remembered to lock it behind him.
Getting to school was fairly easy. He didn’t know Gwen lived this far away so he payed for a bus and got there in no time, hopefully she wouldn’t mind him using her money.
When Senku got to school he waited out front and looked for himself amongst the crowd of students making their way inside.
When he finally spotted her/himself getting closer he had to stop himself from shouting Gwen’s name to get her attention. It would surely look weird to all of them if you shouted your own name. He settled on doing something he will probably hate himself for later.
“Senku-chan~” Senku waved as he did his best to mimic her actions and phrases. He cringed internally when it sounded way too high pitched and childish.
It seemed she forgot what he said earlier about keeping the act up since she went to raise her hand to wave back in return only to stop herself and lower her hand. What she didn’t expect was for her to get into the act immediately.
“How many times have I told you to stop calling me that.” Gwen picked at her ear, shoulders slumped and eyebrows more furrowed in concentration. If Senku didn’t know any better he would have thought he was back in his own body. Is there anything this girl can’t do? Although she didn’t sound quite like he did, could use a little work.
Senku was momentarily stunned before tuning back in to fall into step beside Gwen. It was weird seeing himself in the third person, he looked much taller in Gwen’s body.
Getting to class was easy enough, they both went to each other’s assigned seats. Trying desperately not to look out of the ordinary.
As he waited for the bell to go and for class to start he couldn’t help but wonder how Gwen’s morning was when she woke up.
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Gwen sat up in bed, looked around the room, the walls covered in science projects and equations pinned up on a board that hung askew.
This definitely wasn’t her room.
She wrapped the blankets around herself and tried to fall back asleep. Every five minutes she would wake and and sit up in bed again and repeat the process. She did this for about an hour before it settled in that she wasn’t in her own house, let alone her own body.
Her chest felt lighter, and…something was between her legs that she definitely didn’t have the night before.
Gwen recognized whose room this was, the huge solar system model on the desk was a dead giveaway.
She’s in the body of her classmate Senku Ishigami, her only question was ‘how is this possible?’
Kicking off the blanket and swinging her legs to the edge of the bed she walked into the bathroom. When she stood in front of the mirror she was surprised to see she had no shirt on. Senku’s lean pale body was the first thing she saw, she couldn’t help but stare.
She felt a weird ache in her lower abdomen, something that was pressing on her…
Oh no…
She slowly closed the bathroom door with a click, making her way to the toilet.
It had to be done, there’s no way to avoid it.
“Forgive me…”
She whined internally before loosening the strings to her sweatpants.
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After washing her hands she stepped out of the bathroom with a dazed look.
Never again.
When she went back into the bedroom she found Senku’s phone by the bedside table, connected to the charging cord.
Gwen went and picked it up, looking at the black screen come to life, Albert Einstein’s famous equation as a screensaver. Gwen smiled to herself at just how cliché this boy was.
She looked at the four digit code and realized she didn’t know the password to unlock the phone. Gwen started recounting every interaction she’s ever had with Senku, trying to piece together any four digit number that Senku could have used for his password.
After coming up empty handed she started sifting through his drawers and belongings hoping that this brainiac kept his password written down somewhere in case he forgot.
Who is she kidding of course he wouldn’t forget his password. Not only does he use it everyday but this boys brain has every formula written by mankind memorized.
Gwen groans as her only line of communication of locked off. She looks at the screen again, hoping it will have facial recognition and unlock for her.
3…7…1…9
Huh?
Where did that number come from? Was that…Senku‘s voice in her head?
What an oddly specific number but she thought she’d try it anyway. Gwen typed the number into the padlock and was delighted when it unlocked and brought her to the home screen.
She did it!
Gwen excitedly went to the contacts and began looking for her own number among the others. Finding it fairly easily, he had everyone under their formal name. Well, except “Old man” and “Big oaf” it was safe to assume the last one was Taiju.
Though she wondered who “old man” was. Senku’s Grandfather maybe?
That didn’t matter right now, what mattered was getting ahold of Senku. If her logic was correct Senku should be in her body right now.
She pressed her name and waited as the soft buzzing sound replaced the rooms silence.
After the third ring she could hear her own voice coming from the phone. “Hello?” Sounds like Senku’s been up for a while.
“Senkuuuu! Please tell me what’s going on!” Gwen whined pathetically. All her inner turmoil was finally flooding the gates now that a more mature and responsible person was involved. She was panicking internally from the start and had decided to keep it together until she could find someone else to rely on.
“How that hell would I know?” His voice cut through the air, even while sounding like a girl there was no mistaking it was Senku on the other line.
“Well you’re the smartest person I know! I figured if anyone had an answer it would be you!” Gwen sniffled, tears forming in her eyes. She was barely holding it together.
Senku groaned into the phone. “Meet me at school, and we’ll figure something out.” There was a long pause before Senku added. “And please…try to act normal.”
“Huh? What are you insinuating, Senku-chan? I am the epitome of ‘normal’” Gwen said dramatically, even though Senku wasn’t here to appreciate her flare.
“That’s exactly what I’m talking about. I don’t sound like that and I don’t talk like that. You need to act like me if we want to avoid suspicion.” Gwen could practically hear his blood vessels popping, giggling at the thought of seeing Senku’s irritated face. “See you at school.” The call ended soon after.
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Now they’re both here.
In school.
Surrounded by people.
It was going to be a long day.
The bell rings and everyone went to their designated seats. Senku has to keep reminding himself to keep his legs closed or crossed, girls aren’t necessarily supposed to be sitting with their legs wide open, in a skirt no less.
He looks up at Gwen sitting in front of him, doing better than what he expected. She sat like him, talked like him and even picked at her ear every once in a while like he did. She was scary good at this.
Their morning classes went smoothly since they could keep and eye on one another. The hard part was separating to different classes once lunch was over.
When the bell chimed for lunch break Senku walked up to Gwen before she could leave.
“You need to go to the lab.” He instructed, it was important to stick to his schedule if they wanted to avoid suspicion.
“But I don’t wanna!” Gwen whined, the last thing she wanted to do was stay in one place for long extended periods of time. She didn’t even know what she going to do there, science was Senku’s specialty, she never understood a thing of what he talked about while in there.
“Just take look over some notes and everyone will leave you alone, they usually do when I look busy.” Senku looked through his bag he let Gwen borrow for today, handing her a notebook full of loose papers and written formulas.
“And if they don’t?”
“Tell them to buzz off. Then they’ll really leave you alone, they might be clingy and annoying but they respect boundaries if you put your foot down.”
Gwen furrowed her brows as she debated whether agree to his request. “Fiiiiiiiine…” She groaned as she gave in, clearly not happy about the arrangement. “But that means you have to go and be a social butterfly with other people in my stead, won’t look natural otherwise.”
“Tch! Fine.” Senku gritted his teeth as they both went their separate ways after leaving the deserted classroom.
Entering the courtyard Senku already wanted to go back inside. The hustle and bustle of the many students around him, it was difficult to even hear himself think.
He nearly jumped out of his skin when he felt a large hand press into his shoulder. When he looked over to see who it was he let out a breath of relief.
“Tskukasa! You nearly gave me a heart attack.” Senku places a hand on his chest as he tries to regain his composure.
“I see we’ve dropped the pet names.” Tskukasa says with an eyebrow raised, clearly thrown off at the lack of a “chan” that is normally added to end of his name.
Ah right, he forgot how Gwen always put honourifics at the end of everyone’s name whether she knew them personally or not.
“Just messing with ya, Tsuka-chan!” Senku winked and internally cringed at how childish he sounded while trying to make his voice a higher pitch.
Tsukasa brushed off the abnormality and carried on as if nothing happened. “Everyone was worried when you didn’t show up at our usual spot.”
“Oh…yeah, sorry about that, I seem to be a bit out of it today.” Senku gave a strained smile.
“Did you not sleep well?” Tsukasa was leading him through the crowd, students parting a way for them to walk through with ease. Senku instinctively grabbed onto his sleeve in order to not lose him.
“Not necessarily, just a…rough morning is all.” He said loud enough for Tsukasa to hear him over the crowd of conversations.
When they made it the fountain in the middle of the courtyard he could see a group of people already indulging in a conversation of their own.
Ah geez, guess I’ll have to hold a conversation for a while if Gwen’s chatty personality is anything to go by.
Senku deflates at the thought, all he wanted to do was be up in the lab working on experiments and new inventions.
When they join in with the group everyone’s attention turns to Senku as if they’re expecting him to say something.
Senku looks at them all confused. “What?” He exchanged glances with everyone wondering why everyone got so quiet.
A white haired boy gives an airy chuckle, shifting his blue eyes out from under his yellow hat. “You’re usually very talkative Gwen, anything wrong?” Ukyo says sweetly, that boy doesn’t seem to have a bad bone in his body but is continuously seen with this group of known delinquents and trouble makers.
Crap. Senku doesn’t know how Gwen treats these guys. Is it similar to how she treats Senku or is it completely different?
Before he has the chance to say anything Tsukasa steps in. “Gwen’s had a rough morning, I think it’s best to give her some space until she feels better.” His hand resting on Senku’s shoulder.
Seems like Tsukasa and Gwen have a special bond of some sort, Senku thinks as he spends the rest of the lunch listening to the conversation floats around the group. He nods along and smiles every so often as to not draw suspicion.
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The bell ringing for school for classes to resume is his saving grace. He quickly rushes out of the courtyard and hurriedly gets to his afternoon classes, the further away he was from all of them the better.
The rest of the day went by quickly and easily he managed not to draw suspicion to himself despite his poor acting skills and hopefully everything will be back to normal tomorrow.
Senku grabbed Gwen’s overly accessorized backpack, slung it over his shoulder and made his way to the school entrance to go home-technically Gwen’s home.
He sees his own body waiting for him at the doors, he still can’t get used to seeing himself in the third person, it’s starting to creep him out. Gwen waves to him as they fall into step next to each other, starting their journey home.
“How was your day?” Gwen chirps using his own voice, it startled Senku so much he trips and keels forward hitting the ground.
“How the hell did you do that?” Senku struggles to stand up, still unnerved.
“Hm? Change my voice? It’s quiet simple really it’s all about using different parts of your vocal cords, I can sound like anyone.” Gwen demonstrates by pressing her throat in a certain way and mimicking Chromes voice. “Science is so baaaaaad!”
“Heh, you sound just like him.” Senku chuckles as they continue their way down the street. “Going back to your question, my day was pretty uneventful despite the whole ‘body swap’ thing.”
“Really? I thought my life was pretty thrilling for a teenage girl.” Gwen fake pouts. “My day was pretty chaotic now that I think about it.” Putting a finger to her lips in thought.
Senku raises an eyebrow at this, what could have possibly happened for it to be chaotic?
“Really? How so? Did the guys give you any trouble?”
Gwen didn’t want to tell Senku that while she was taking his place in the lab Chrome was more excited than usual and wanted to experiment with some new liquids that came in. Gwen didn’t know anything about them but Chrome kept going on with childish enthusiasm, calling them long overcomplicated names that she’s couldn’t catch. The boy was so excited he started pouring one into the other without knowing what they did. Gwen could only watch as pink fizz started to pour endlessly out of the bottles. It took all of lunch to safely clean up and dispose of. Although everyone was unharmed Chrome got a whack to the head from an angry lioness grumbling something about being careless under her breath.
“Yeah…something like that.” Gwen laughed nervously.
They arrived at Senku’s house and he instinctively went to the front door. Gwen had to tap his shoulder to remind him he doesn’t live there right now. “Hopefully this doesn’t last long, I sure don’t want to get used to this.” He rubbed the back of his neck as he slipped past her and walked out to the sidewalk. “See ya around.” He lifted a manicured hand and waved his goodbye.
Gwen smiled as she turned around to go inside the house she woke up in this morning. It was quiet but not the kind she was used to, this kind of quiet held warmth. She could see the sun fill the room with a comfortable glow, a place of good memories.
Gwen took her time looking at all the photos hung up on the wall, and there was plenty. One of Senku winning a science fair, another one of Senku building a rocket in his backyard, another one of Senku winning a different science fair only this time he looked older.
She looked at all of them. The cute ones when he was a baby, the ones with him and Taiju having a sleepover. The one she looked at the longest was one with Senku and an older man. She recognized him to be Byakuya, Senku’s dad. In this photo they are both wearing a kimono, looking up at the fireworks in awe. She assumed this had to be taken during a festival given the fox mask pushed to the side of Byakuya’s face. It must be a fond memory for them to share.
Gwen went upstairs and stayed there for the rest of the night. Byakuya didn’t come home so he must be working late or away for a few days. Gwen continued to stare at the ceiling full of sticky glow-in-the-dark stars that looked faded.
To be completely honest she hoped this experience would bring her and Senku closer together.
But she knows that’s just wishful thinking. A wish to be made on a fake star like the ones above her.