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Yuuki let out a sigh, as she stared at her math homework. But, try as she might, simply staring at it did nothing to help her. It wasn't going to go away if she did nothing, and it was already midnight. With it being due tomorrow, or well, today, she couldn't keep putting it off any more.
Ah, another all-nighter, it seemed. Whatever, as long as she gets something down, it was better than nothing, right? She probably didn't even need to know half of this anyway. It was all pointless really, especially if she was going into fashion design. But still, she needed to pass this class, or else her parents would really nag at her for it. They were certainly quite the complaining type. It got on her nerves nearly all the time. Especially when they complained about Mizuki. Her dear little sister.
Mizuki had only just turned ten, and yet her parents acted as if she needed to know everything. Their constant criticism, over and over, really infuriated Yuuki. Her poor sister, her poor little Mizuki. She was practically defenceless when Yuuki wasn't around to help. A heaviness grew in her heart when she thought about it. If only she could do more. If Yuuki had the money to, she'd get both her and Mizuki out of here. Surely running away was better than this, right? Ah, well, not much she could do about it at the moment. She just needed to get this over with. And then, she could finally sleep her worries away.
Turns out, the questions weren't actually as hard as she thought. With some rushing, she managed to get most of them finished at a reasonable level. Whether they were correct was a different matter, but at least she finished it. Yuuki stretched her arms before letting out a yawn. Ah, she really needed to go to sleep…
Her bedroom door slowly opened. Her eyes widened, looking over to see who it was.
"Onee-chan… wait, why are you still awake?" Mizuki asked, peering her head into her sister's bedroom.
"I could ask you the same thing, Mizuki," Yuuki smiled. "How come my little sister is still awake?"
Mizuki looked away for a moment, before gathering the courage to speak. "I… I couldn't sleep. I tried really hard, but I couldn't. Then, when I asked Mom and Dad if I could sleep in their bed, they told me I was too old to be doing that. And that I was too big to be sleeping with them in their bed."
Yuuki let out a sigh. Stupid parents. Thankfully, she was already finished with her homework.
"You can sleep with me in my bed, that's what you were gonna ask, right?" Yuuki asked.
Her sister nodded. Yuuki couldn't possibly see how she was 'too big' to sleep in her bed, she was so tiny, so adorable. Regardless, Yuuki got onto the bed, gesturing for Mizuki to lay beside her.
"Onee-chan, why were you still awake?" Mizuki asked as she got in the bed.
Yuuki put the blanket over her sister's body before replying. "School stuff, don't be like me, okay? You shouldn't leave things to the last minute like Onee-chan does when you go to high school."
"Mm. Okay," Mizuki mumbled. "Can Onee-chan hold me?"
She'd do anything for her little sister. Mizuki looked shy, looking away from her as she asked. How could she say no to that face of hers? Her sister was so adorable, Yuuki didn't understand what was wrong with their parents. How could they scold someone with a face like hers?
"All right, Mizuki, c'mere, I'll keep you safe," she whispered, pulling her sister's body closer to her. "You trust Onee-chan a lot, don't you?"
Mizuki enthusiastically nodded, snuggling up to her sister. "Mm! Onee-chan's the best."
Ah, she really was adorable. Hearing Mizuki praise her always brought a warm feeling in Yuuki's heart. Her little sister's body felt so warm. Holding her like this, she could feel her sister's heartbeat. They were so close to each other. It was peaceful. Relaxing.
The warm feeling however, didn't only stay in her heart. Her whole body grew warmer. She wanted to view Mizuki in a normal light, she really did. She desperately really wanted to, she swore she didn't want to hurt her.
But, from now and then, she had thoughts would pop in her head. In the back of her mind, it lingered. Whenever she saw her sister's soft bare skin, a part of her wanted to bite it—
Yuuki gulped. She had to ignore those thoughts. She had to, Mizuki only had her. She needed to be someone safe for her, someone that Mizuki could rely on. Yuuki shut her eyes closed, pushing those thoughts away.
"Onee-chan, you seem so tired," Mizuki mumbled. "Even more tired than me…"
Yuuki held her sister tighter, trying to ignore the thoughts that consumed her. "I just have a lot of things on my mind. Mizuki, how about you get some rest?"
Mizuki didn't respond, instead closing her eyes. She was a good kid. Yuuki hoped she'd live a happy life, one where people love her for who she was.
"Onee-chan, I can't sleep if you're holding onto me that tight, it's a bit too much…" Mizuki whispered, sleepily opening her eyes.
Eh? Was she really doing that? Yuuki loosened her grip. She hadn't even realised, but her hands had been digging into Mizuki, uncomfortably pressing against her skin.
"I-I'm sorry, I must've, well, I guess I didn't realise I was doing that. My apologies, Mizuki," Yuuki apologised. She gently patted her sister's head, hoping to not hurt her again. She didn't intend on doing that.
"It's okay, Onee-chan, I know you didn't mean to."
Yuuki couldn't help but smile. Mizuki was so forgiving. Perhaps that was something her sister needed to work on. Not all people deserved her forgiveness. Especially not their parents. But then again, she was too young to know these things. Maybe it was better if she didn't know about that yet.
Mizuki's face leaned, closing the distance between them. Huh? Yuuki flinched, as she felt soft lips press against her cheek. Her eyes widened as she processed what Mizuki had done. What?
"Um… that was me saying thanks, since you've always been there for me, Onee-chan," Mizuki mumbled as she leaned back, making sure to avoid eye contact with her.
God, she really was cute. The thoughts in the back of her mind were getting louder by the second. It wouldn't hurt to give her a kiss back, right? Just an innocent kiss, nothing more.
Yuuki pulled her sister's head close, before gently giving her forehead a kiss. That was fine, she thought. If she wasn't hurting her sister, things were fine.
"Hehe, that tickled, Onee-chan," Mizuki softly giggled.
Whilst Mizuki laughed to herself, Yuuki realised her hand was under Mizuki's shirt. When did that happen? It could've been whilst she was laughing, Yuuki's hand had somehow slipped under. Should she move it… ah, but her skin felt so soft. It wouldn't hurt to keep there, maybe. Yuuki's hand slowly edged higher and higher. Why wasn't she saying anything?
"Onee-chan, your hand tickles," Mizuki snickered as Yuuki's hand had gone completely under her shirt.
So cute.
"Your hands are so much bigger than mine, Onee-chan, I hope to grow up to be just like you!" Mizuki rambled on, unaware of her sister's eyes on her skin.
…Hmm.
"Mizuki, you can keep a secret, right?" Yuuki whispered.
Mizuki nodded. "Of course!"
"Then, how about I show you something more… fun?"
Just once. She wanted to try, just once. Or, maybe more than once. But if she told herself once today, then she wouldn't feel bad afterwards. Even if it was just a lie.
"Yeah!" Mizuki said, speaking in a quiet voice to not wake their parents up. Her eyes were bright with excitement.
Ah, her little sister really was the cutest thing in the world.
"Can I take off your pants, Mizuki?" Yuuki asked.
"Huh? Uhh, okay," Mizuki replied, before letting her sister pull her pants down, putting them away to the side.
Now that she was exposed down there, Yuuki couldn't help but stare at her sister's adorable little dick. Whenever she helped Mizuki take a bath, she couldn't resist staring at it. It probably needed to be touched a bit. Mizuki needed someone to take care of her.
"Now, I'm going to make you feel really good, but you have to stay quiet for Onee-chan, okay?"
Mizuki nodded in response. If she couldn't stay quiet, Yuuki could always cover her mouth with her hand. But, with how far her bedroom was from her parents' bedroom, she was certain they couldn't hear them. Eventually, Yuuki's hand moved towards her sister's dick, wrapping her fingers around the short length. God, touching it felt so nice. It was so small, it was practically hidden when she wrapped her hand around it. Slowly, she started stroking it, checking her sister's face for any sign of discomfort.
"Doesn't it feel good, Mizuki?" Yuuki asked.
"I-It feels weird, Onee-chan," Mizuki breathed out, her hips twitching.
"But it's the good kind of weird, right?" she asked again, continuing her pace. "Right, Mizuki?"
Mizuki covered her mouth, as she continued stroking her dick. Her efforts to stay quiet were so cute. Her little sister had her mouth covered, and was even hiding her face in the crook of Yuuki's neck. But even with all of that, some whimpers still managed to escape, as Mizuki's body squirmed.
"It's-Ahh! Good, it's good, hahh, Onee-chan, it's… so warm," Mizuki whimpered. She sounded so perfect like this.
"Onee-chan is making you feel really good, isn't she?" Yuuki asked, whispering into her sister's ear. She smiled as she felt Mizuki's cock twitch. Her sister's cries only encouraged her to go faster. It was okay if she got hurt a little… it would teach her to be stronger as she grows up! That logic was perfectly sound, maybe.
"I love you so much, you know that, right, Mizuki?"
"Mmm! Y-Yeah, ahh! Onee-chan, I think it's too much," Mizuki cried, as tears roll down, dripping onto Yuuki's shirt.
"Hey, Mizuki, can you look at Onee-chan for a second, please?" Yuuki asked.
Mizuki pulled away from her sister's neck, looking at her with glassy eyes. She still had tears rolling down her cheeks. Everything about her was simply the cutest. Mizuki let out a yelp as she felt her sister's tongue on her face. Yuuki licked away her tears, savouring the taste. She hated to admit it, but Mizuki also looked really cute when she cried. Only she could make Mizuki cry like this, no one else. No one else was able to wipe away her tears, to lick them away and to comfort her. Only she could.
"Huh, Onee-chan?" Mizuki asked, confused as Yuuki kept licking her tears.
"Your tears taste so sweet, everything about you is adorable," Yuuki muttered, her strokes getting even faster. "You're such a good girl, Mizuki."
"I am? R-Really?" Mizuki stammered. "Onee-chan, stop, it's too much, ah! Wait, please, ngh, Onee-chan, I—"
Mizuki's entire body tensed, as a long moan escaped from her mouth. Thankfully, it was mostly muffled by her hand. Yuuki eased her sister through her climax, her strokes slowing down, until eventually stopping. When Yuuki eventually looked down, she found a wet patch on her pants that was covered with her sister's cum. She definitely needed to switch into a different pair of pyjamas, but at the same time…
Yuuki swiped her finger over the cum, before bringing it to her mouth to taste.
"Eh? Onee-chan?!" Mizuki quietly gasped. "Why are you tasting that…"
Yuuki roughly pulled Mizuki in, slamming her lips against her sister's, her tongue shoving its way inside. Their tongues swirled against each other, and Mizuki had no way of fighting against it. Her older sister forced Mizuki to taste herself.
After what felt like an eternity, Yuuki pulled away.
"Doesn't Mizuki taste good?" Yuuki cooed, seemingly overjoyed by the kiss they shared.
"Mm…" Mizuki responded, looking down at the mess she made on her sister's pants.
"Ehehe, you did so well," Yuuki chuckled, giving her a kiss on the cheek. "Just gonna change out of this, I'll be right back!"
Mizuki looked away as Yuuki began to change. She also pulled her pants up, and caught her breath again. Something in her chest felt weird.
"I'm back, Mizuki, did you miss Onee-chan?" Yuuki smiled.
"Mmm, yeah," Mizuki replied. She didn't know what she felt. Maybe it was that.
"You're such a good girl," she whispered, as she held Mizuki close to her body. "Now, you should really get some rest, okay?"
Mizuki nodded, trying to relax herself in Yuuki's arms. But, her older sister's embrace didn't feel right and she couldn't tell why. The warmth was still there, it never left, but something else was mixed in there too. Her sister's arms felt strange now. However, Mizuki was too sleepy to identify what it could be. She should just go to sleep, perhaps. The feeling would probably go away by the time she woke up. And so, Mizuki closed her eyes, trying her best not to think about it.
Her sister was still her sister after all. Even if she had violated her.