Okay, here's another Free! Oneshot except this time it's basically AU because Gou is the older sister and Rin is the younger sibling.

So here's sixteen-year-old Gou with Rin, Haruka, and Makoto being twelve while Rei and Nagisa are eleven.

Oblivious Gou/Iwatobi Boys

The Act of Sharing

Sometimes Gou wondered how she got herself into these messes.

Walking along the sidewalk towards the aquarium, the teenager couldn't help but yawn from the lack of sleep she has been suffering due to exams, and wished nothing more for her to be back in her own bed.

A tug on her hand alerted her though of the exact reason why she wasn't allowed to journey into the realm of slumber.

"Onee-chan! Let's look at the sharks together first!" Rin exclaimed excitedly to his older sister, tugging her hand along towards the entrance. Despite her tired state of mind, she couldn't help but smile fondly at her younger brother.

"Ah! Rin-chan—we have to get tickets first before we can go anywhere." She reminded the young boy of twelve. Her eyes then widened when she caught sight of one of her other charges causing shenanigans, "Haruka-chan! Don't dive into the dolphin tank!" she cried flailing as the dark haired boy was starting to take off his clothes. Pulling Rin along, she rushed towards Haruka and dragged him away before he could get them kicked out of the aquarium before even getting in.

"Aw, Gou nee-chan! Haru-chan was going to swim with the dolphins!" Nagisa whined, pouting cutely. Gou sighed and resisted the urge to rub her temples.

"Nagisa-chan, I told you to call me Kou!" she said exasperatedly as the blonde smiled cutely up at her. She inwardly had to remind herself that while he may be an adorable boy on the outside, inside he had the mind of a devil.

"But Gou nee-chan! That's your name." Nagisa told her, Gou's eye twitched at the smartass comment. He knows she hates her name with a passion—he just refuses to comply to her wishes of not being called by it.

"Onee-san, will we be able to go in now?" Rei questioned her, fixing his glasses—the poor boy had a pair that was too big for him. Makoto also looked up at her while—bless his soul—keeping an eye on Haruka before he decided to go jump in the dolphin tank again.

"Well, since you're all so eager.." Gou sighed out, readying her wallet to pay for all of them, and thanking Kami-sama she had a job to actually pay for them all and not dent her wallet in the process. Their mother had only given her money for food inside the aquarium so it was up to Gou to pay for entrance fees and maybe some trinkets if they were good enough.

A mournful look overcame her when she remembered that she wasn't even supposed to be entertaining her younger brother and his friends today, but rather going out on her date with Seijuurou—or the "first date that would finally come"

It was kinda sad on how many times they've tried going on a date and all of a sudden her younger brother and his friends roped her into babysitting them.

Choosing to block out this morning's memories of her baby brother jumping in her bed while Nagisa poked her as Rei rambled about the probability of it being a sunny day and Haruka and Makoto pulled out her clothes for the day, she paid for each of their tickets and they journeyed inside.

Rin let go of her hand and raced inside with Haruka and Nagisa as Makoto and Rei stayed closer to her, acting more behaved. This time Gou did rub her temples as she caught up with the three. Gazing down at her charges, she got their attention by clearing her throat.

"Okay, there are two ways on how we can do this. We can all stay together and take turns checking out what everyone wants to see or—provided you all are responsible—we can pair up and you and your partner get to check out whatever exhibit you want and we'll meet up back here at one for lunch. Which one do you guys want to do?"

They all looked at each other and then back to her, seemingly deciding something, and said "Partners." simultaneously.

"Okay then!" Gou smiled at them, "So who wants to be paired with who?"

Her eyes widened and she blinked a couple of times when they all pointed at her.

"Kou/Gou nee-chan/Onee-san/Onee-chan!" they all said, staring at her. Then, realizing that they all chose the same person, turned to each other and stared each other down.

"She's my sister so I should get her." Rin glared at them.

"No fair! I want to show Gou nee-chan the penguins!" Nagisa complained to him.

"I don't really think it's fair you always get to partner with Gou nee-chan, Rin." Makoto added. "Why don't you go with Haruka since the dolphins and the sharks are close to each other?" he suggested.

"Rin will scare the dolphins away with his shark teeth." Haruka told Makoto bluntly. "Kou's nice so they'll like her."

"Eh? Who are you saying has shark teeth, Haru?!" Rin turned his glare to the black haired boy who only shrugged.

"Alright, enough!" Gou told them, stopping any more bickering from breaking out. "We'll all just stay together and check out every exhibit we want to explore, okay?"

Each boy nodded in agreement but as she turned away, they all sent each other a spiteful glare.

It wasn't even lunch time and Gou was ready to call it quits.

She didn't think it was possible to have so many incidents in the span of a few hours, but she clearly underestimated the mischief preteens can get into.

First they went to the whale tanks with Rin spitting spit balls at the glass tank when Makoto took her hand to lead her around it, then when they were at the "touching sea creatures" exhibit Rei was next to her as they were petting a starfish and Nagisa bumped (pushed?) into him and Rei's hand got stuck into a sea urchin, then at the penguin pen Nagisa let all the penguins lose to "show her" since she was in the back to tend to Rei while Rin, Haruka, and Makoto stayed close, then when they were at the dolphin tank Haruka yanked her into the water away from all her other charges as "Rin's shark teeth is scaring the dolphins so Kou won't be able to see them if she stays close", and then finally when they were at the shark tank with Rin guiding her along and being affectionate, all the boys actually pushed him into the shark tank.

Needless to say, she had a lot of apologizing to do towards the manager and owner and thanked Kami-sama multiple times that no one was harmed or else she'd be grounded.

Currently, they were all outside where the aquarium provided a playground for the kids who attended there. Gou was laying on the grass ready to sleep the day away under the sun. She was so exhausted that she could barely keep up with her replies to Seijuurou via text, before she stopped replying all together.

Laying an arm over her eyes to shield her from the sun, Gou readied herself for a nap.

Or at least she would have if a wet finger wasn't poking her cheek.

Cracking her eye open, she found herself staring up at Haruka, who was peeking over the fountain rim he was swimming in (not with permission of course but since when did that stop Haruka from swimming?) and staring down at her.

"Haruka-chan, why are you in the fountain…?" she sweat dropped.

"Because there's water, Kou." Haruka replied simply, making Gou sigh and close her eyes again. Out of all Rin's friends, Haruka was the least verbose and blunt when he did decide to speak.

"Kou," he called her attention again, "why are you sleeping?"

"Cause I'm tired, Haruka-chan."

"Why are do you call me, 'Haruka-chan?'"

"Eh?" Gou blinked at him. "Because that's your name." she stated, wondering if Haruka has finally drowned his brain cells with how much time he spends in the water.

"No," he shook his head, "Why am I called 'chan'? I'm a boy."

"I know you're a boy, Haruka-chan." Gou giggled. "I call you all with 'chan'. There's nothing wrong with that. It's like I'm referred to as 'Onee-chan'." Gou explained. Haruka averted his eyes to the side and sunk a little more into the water.

"I don't like calling Kou 'Onee-chan'. It shows she's older than me." Haruka replied quietly. Gou yawned, feeling her eyes drooping more from tiredness.

"Hm?" she yawned again "But I am older than you…" she trailed off and fell asleep, the warm sun caressing her features and the light breeze was like a soothing lullaby. Meanwhile, Haruka watched her before getting out of the water and putting his clothes back on over his swimsuit and settling down next to Gou. His arm placing itself across her stomach in an affectionate manner.

"But I want to hurry and grow up, Kou."

Nagisa hummed as he journeyed away from the playground after becoming bored with teasing Rei and pushing him down the slide when he wasn't looking. Spotting the familiar Matsuoka hair of Rin's older sister, Nagisa grinned excitedly at the idea of spending time with Gou when the others weren't around. Upon coming closer though, he found that Gou was stolen by the realm of slumber and Haruka was next to her, his arm laying across her stomach.

Haru-chan, you sneak. Nagisa stuck his tongue out at him. For once he wanted to be the one who stole Gou first, but then again, he supposed that with only Haruka in her presence it wasn't so bad. Plus, Gou had two sides for snuggling and Nagisa didn't mind sharing for now.

With that thought in mind, Nagisa grinned and settled on Gou's other side, snuggling into it like a kitten. He brought her arm around him and laid his head on her stomach where Haruka's arm wasn't and engulfed her in a hug.

A nap with Gou wasn't a bad idea at all.

Rei scowled as he nursed another bruise courtesy of Nagisa. Sometimes he questioned why he was still friends with him, but he knew Nagisa had his good points as well and that reminded him that while Nagisa was a bully at times, he was also a good friend.

His good side was just very very miniscule.

Rei fixed his glasses and walked towards the fountain, intent on getting some peace and quiet away from Nagisa's torture for a while (wherever he is). He remembered seeing Rin's older sister Gou there. At this, Rei's cheeks turned pink. She was always so nice to him and didn't care that he tried to calculate everything like some other people did. He wondered why no girls his age could be like her: understanding, kind, and a joy to be around.

Gou was just beautiful to him—he could clearly see it and that's why he liked her so much.

Unfortunately, he wasn't the only one to see that beauty…

Finally reaching to where Gou was, his eyes widened when he saw Haruka and Nagisa each sleeping at her sides. Haruka had his arm across her stomach while on her left Nagisa was buried into her side and on her stomach like a cat.

He fixed his glasses again, his thoughts running. Most likely Rin was off somewhere and didn't know about this because he would throw a fit that his friends were hogging his "precious Onee-chan" from him.

Well, if my calculations are correct—which they are—then most likely Rin won't be around for a while… with that, his cheeks colored pink and he trekked closer to the slumbering trio. Settling above Nagisa by her head, Rei let the warm air and the gentle breeze lure him to sleep.

Wonder where everyone is, Makoto wondered as he journeyed around the outside, I hope Haru isn't swimming in another tank or the fountain. With a sigh, Makoto searched for Haruka in hopes that he wasn't right. Kami-sama only knew that Gou would pass out from fright like earlier when Rin was in the shark tank.

I hope Gou nee-chan isn't too exhausted. Makoto shook his head. To be honest, he felt a little guilty that they take up Gou's time, but they couldn't help it. It was something they all never brought up, but they all knew they liked Gou a lot and didn't want to share her with anyone.

He remembered the first time the sixteen-year-old came with Rin to swim practice at their club. She was very outgoing and caring about Rin who, despite pushing her away in an effort to appear more manly, adored her as well. Finally putting a face to the name of Rin's older sister, his friends were fascinated by her. She also showed she supported them as well as her younger brother and was willing to help them if they ever needed it. Gou was not unkind and listened to their problems and fears without judging them and treating them like children—it made her special to them.

But eventually she's going to leave, Makoto thought sadly, Gou nee-chan is older than us and has her own life after all. We can't hog her forever. She's going to leave us behind.

He remembered bringing this up to Haruka once—the closest thing that will ever be said to them admitting their feelings out loud to another. Haruka only looked at him blankly before fixing his goggles.

"She's only four years older than us. No big deal. We can catch up." and dived into the water.

His memories were interrupted by the sound of light snoring. Approaching the fountain, he was shocked to find Gou lightly snoring with Haruka, Nagisa, and Rei sleeping all around her.

Rin must be somewhere far off…. Makoto thought, contemplating if he should go find him. Nonetheless, the sight of Gou sleeping peacefully and the opportunity to be close to her made him rethink that. They were all usually competing for her attention—just once did Makoto want to be next to her without interference.

With that thought in mind, Makoto settled down on the other side of her head above Haruka and let himself fall asleep, his head touching Gou's and feeling at peace.

"Where is everybody?" Rin scowled, looking for his friends. Not finding them in sight anywhere, Rin decided to look for his older sister and see if he can convince her to spend time with him (which won't be hard since she adores him). He liked it when he and his friends could take his Onee-chan places but sometimes it got annoying when he couldn't have her to himself.

Rin was used to being spoiled by Gou ever since he could remember. Bedtimes stories, playtime whenever he wanted with her, her telling their aunts and uncles they would get married so no one can take him away from her—his entire childhood consisted of Gou. Call him selfish all you want, but it is a baby brother's duty to be the number one in their older sister's lives and the baby brother has to protect her from everything evil or that can steal her away.

Like Seijuurou for instance.

That guy seriously needed to take a hint. Ever since Gou and him did a project at their house (with Rin spitting spitballs at him from across the room), the guy has wanted his sister's attention. Gou didn't see the danger Seijuurou posed and could steal her away, but Rin did, and he wasn't allowing it.

It was bad enough his friends wanted to steal her too. Rin knew he would always be Gou's pride and joy but seeing all of these boys want Gou's attention didn't sit right with him. There had to be some rule against your friends and anyone else you deem unworthy to want your sister's attention! He was sure of it.

Spotting the fountain in the courtyard, he figured he might at least find Haruka since he knows Haruka loves everything water. Coming closer though, he was met with a sight that made him nauseous.

There was his precious sister and his—traitorous, he supplied—friends all sleeping soundly with them all snuggled up to her. Haruka slept on one side, his arm around her in a way that eluded the feeling of a man holding his loved one rather than a child seeking comfort, Nagisa on her other side snuggled into her possessively, Rei by her head above Nagisa and sleeping on her Matsuoka tresses while Makoto was on her other side above Haruka, their foreheads touching.

Looking at it made Rin want to vomit.

He never liked having to look at his friends or Seijuurou show affection for her. To him it seemed wrong in a way. Ever since their dad died, he was the man of the house. He was supposed to take care of her like she cared for and loved him.

Facing the reality that Gou might leave him one day and one of his friends or some other person might take her away was like a slap in the face.

Coming closer, he gently climbed on top of Gou and laid his head on her chest like he always did when he had a nightmare and he went to her for comfort. He felt Haruka and Nagisa's arms under his stomach but he didn't care. Looking at her peaceful face, he had to realize his biggest fear.

I don't want you to leave me.

Snuggling into her, the twelve-year-old took in his sister's scent of strawberries and let it lure him to sleep, dreaming of all his friends, his father, and most of all his older sister smiling down at him.

Haruka stirred when he heard something vibrating. Cracking his eyes open, he became aware of a weight on his arm that was laying across Gou. Focusing, he found that Nagisa, Rei, Makoto, and Rin must have all arrived and joined Gou and Haruka with their nap.

Why is Rin sleeping on my arm? Haruka wondered. The vibrating then caught his attention again. Deciding to ignore Rin for now, he pulled his arm out from under the boy and searched for the item that awoke him from slumber. Looking towards Gou, he found the noise was coming from her pocket. It must be her phone.

Gently removing the phone from her pocket, and not minding Gou's privacy, opened it up to see there was a text from someone called "Seijuurou". Raising an eyebrow at the text and frowning, Haruka turned to look at his sleeping companions.

Kou must be worn out if she hasn't woke up to the sound of her cell phone… Haruka thought before turning to Rin and poking him.

"Hm? Wha?" Rin asked disoriented.

"Who's Seijuurou?" Haruka asked, not bothering to allow Rin to become more awake. At the name, Rin's eyes widened.

"Seijuurou? Why is he texting her?" Rin asked, fully awake. Haruka shrugged and showed him the text.

"I didn't understand what he was saying so thought I should ask you." Haruka said. "Isn't Seijuurou the one that wants to hang out with Kou all the time?"

Rin nodded, not really paying attention to Haruka while he read the text message. His eyes narrowed as he started typing a reply.

Gou yawned and cracked her back a bit, feeling a lot better after a nap. Rin held her hand while Nagisa held her other as they left the aquarium. Strangely, there was no mishaps after lunch and the boys seemed to have learned to get along.

"Onee-chan, is it okay if Haruka, Rei, Makoto, and Nagisa stay over?" Rin asked her. Gou blinked at him.

"Eh? Well that's up to mom but it's fine with me, Rin-chan." Gou smiled. Rin grinned back at her excitedly.

"Great! If mom says yes can we all watch a movie, Onee-chan?" Rin asked. Nagisa perked up at that.

"Yay! I wanna watch a movie with Gou nee-chan!"

"Can we Onee-san?" Rei asked politely, fixing his glasses. Gou had to laugh at their enthusiasm.

"Sure! But what movie?" she asked them. Haruka and Rin looked at each other before replying.

"Harry Potter."

Turns out Rin and Gou's mother was okay with the sleepover since she finds Rin and his friends to be well behaved and they were so adorable. With permission confirmed, the boys dragged Gou to the living room where they gathered tons of blankets and each found a spot to snuggle with her (to which Mrs. Matsuoka cooed and took a photo without the boys noticing). Placing in the final Harry Potter movie installment, Gou began snacking on her popcorn and her eyes were glued to the screen, not noticing the boys sending each other the occasional glare when one of them snuggled too close to her or messages of communication through locking eyes.

It was in the middle of the movie when Gou started dozing off again (as it was a rather slow part), but then blinked them open when she found her little brother and his friends pointing their fingers at her and saying "Avada Kedavra!"

"Eh?" Gou just blinked at them. Why are they casting the killing curse on her? Did they want her to play dead?

"Did it work?" Nagisa asked.

"Of course it did!" said Rin. "Right Onee-chan?"

"Well… I'm not really dead." Gou giggled at them.

"It's not supposed to kill you though, Kou." Haruka told her.

"But Haruka-chan…. " Gou started confused. "That's the killing curse. That is what Voldemort uses to kill people."

"Why would we kill Gou nee-chan?" Nagisa asked confused as her. "It was supposed to kill your virginity!"

Wait.

WHAT?

Gou stared at them like they all grew a second head.

"Erm… what?"

Did her brain just break?

"According to my calculations, it should've worked." Rei said, fixing his glasses again. Makoto looked worried.

"Maybe we should try again?" he suggested.

"Good idea." Rin said, getting his finger ready to point at her again. "Ava—"

"Rin-chan! Stop!" Gou shouted, grabbing his wrist. "Where did—what—How did you get an idea like that?" she spluttered.

"That's what Seijuurou said he was going to do to you!" Rin told her earnestly. "He said if you wanted to watch Harry Potter with him tonight he would see if you wanted him to Avada Kedavra your virginity!"

Oh. My. God.

Her face erupted into a giant blush. Not only did Seijuurou's words make her feel embarrassed but the fact that her little brother read something of hers that Seijuurou was flirting with her with was even worse.

Oh god, what if Mom finds out? She'll think I'm sleeping around when I'm not! Gou panicked in her mind. Not to mention her mother would skewer her alive if she found out Rin was being "corrupted by her"

"That—um—it's not—" Gou babbled, too busy thinking about how to explain to her mother about how Rin knew what sex was to be angry that he intruded on her privacy.

"Yeah! Exactly!" Rin nodded, glad his sister got his point. His eyes then turned curious as they stared up at her.

"By the way Onee-chan, what's a virginity?"

Each of their curious faces was the last thing she saw before she promptly fainted.

Seijuurou hummed as he played some more of his guitar. His phone buzzing brought him out of his musings when he saw it was from Gou. Grinning excitedly, he eagerly opened his phone to see her embarrassed reply to his flirt and hopefully acceptance to watching Harry Potter with him tonight (he knew she loved Harry Potter with a passion and if Gou was going to be his girlfriend, he had to know what she liked).

However, the reply that greeted him only made him look at his screen in shock instead.

Dear Seijuurou,

This is Gou's little brother Rin and I'll have you know the only ones who are permitted to "Avada Kedavra" my sister's virginity besides me is my friends so leave Gou alone.

Sincerely,

Gou's little brother who's gonna beat your face if you come near my sister

There you have it! I kinda want to do more of these, but we'll see how it goes. Yes, Rin is so evil lol

See ya Next time!