Chapter 4: Descent into Simplicity

Xinyi mewled as she woke up somewhere warm and soft. Mmm… So comfy… So happy… so… mmm where am I…? She fluttered her eyes, and looked up to see Yeji’s smiling face. “Sis…!”

“That’s right, my baby sister.” Yeji sighed, so slowly sliding her nails through Xinyi’s hair to perfectly tease her scalp. The smaller, rounder woman moaned as her eyes crossed and her mouth opened into a perfect, adorable ‘o’. It fit perfectly on her round face, and below Xinyi’s adorably hazy eyes. “Did you forget that you crawled into my bed last night when you couldn’t sleep? You were so pitiful, asking me for cuddles with those big eyes of yours…”

Xinyi’s cheeks burned, and she tried to hide her face in Yeji’s chest.

She couldn’t remember, but she knew that didn’t mean it hadn’t happened. Her big sis was always looking out for her, always taking care of her, and there was no doubt in her mind that Yeji would never lie to her.

Yeji’s thigh slid between her own, and Xinyi giggled as she rubbed her slick lower lips down against her big sister’s smooth, warm thigh. She wasn’t naked, but the tiny thong, more lace than anything else, was buried in her slit and did nothing to stop her pouty lips themselves from pressing against the other woman’s leg.

As a part of helping Xinyi’s wardrobe better reflect her proper place as Yeji’s younger sister, she’d started insisting Xinyi only wear the smallest, frilliest panties. The cleavage of her tops dipped lower and lower, exposing more of the woman’s heavy breasts to her big sister’s hungry eyes. Xinyi enjoyed the attention, and the certainty that she was doing the right thing. Yeji was always looking out for her, and wearing so much pink also felt so appropriate.

It was cute, just like she was cute! It was girly and soft, just like she was girly and soft! Yeji was so smart, and for the past couple days, Xinyi hadn’t been feeling all that bright at all.

Doing computer things at work hadn’t been hard, but any time she tried to do anything else she inevitably found herself giggling and rocking on her heels or playing with a lock of her hair or staring blankly off into space.

Maybe at first it had been worrying, but by now Xinyi was all too happy to giggle that away.

If anything went wrong, she knew that Yeji would solve it.

“Mmm… Sis… My… big… sis…” Xinyi yawned adorably, pressing her breasts against Yeji’s willowy-yet-athletic body. Her hips moved idly on their own, rubbing with a building insistency for more of the delicious friction that had her eyes rolling back into her head. “Sleeping with you makes… everything better… maybe I should just… sleep in here tonight…? I forgot which room was mine when I got home yesterday, so if you just tugged me to bed when you went to sleep it would be like… a lot easier…!”

Yeji purred, slowly nodding as she reached down to grasp a handful of her little sister’s plush ass. Her nails sank in deep, the sharp pinch of her nails only adding more pleasure for her squirming little sister. “Didn’t we talk about that last night? Is my simple little sister forgetting things again? You’ve just had so much difficulty thinking lately… maybe you should let me do more of that for you, too.”

Xinyi quivered, her thighs clenching that much tighter around Yeji’s thigh. “L-let you… d-do that too…” Her eyes hooded, her mouth moving so slowly as her hips continued their pace without pause. She shivered, from the top of her head down to the tips of her toes, a low, loud moan slowly escaping her lips. “Letting you… think for me… That… that sounds so…”

Like something I heard in a dream… a dream where I woke up giggling and cumming… Ohhh… Xinyi groaned, grasping tight at Yeji’s back as more pleasure wracked her body and mind.

The smaller woman couldn’t remember her big sister’s nightly trances, or the way she’d spent so much time the night before with her head in Yeji’s lap. She couldn’t remember the many times Yeji had whispered how nice it would be to let her take control, to be dumb, and simple, and small when she wasn’t doing important work for Accelerant. She couldn’t remember how strange it had felt at first to be giggling so much, only how good it felt every time she let Yeji make a decision for her.

She’d never steered her wrong. She’d always looked out for her. She’d always made sure she was happy and cared for.

Xinyi came against Yeji’s leg, crying out pitifully as she finally stopped shuddering. “I… want you to… think for me… Mmm… I… don’t think I would have wanted that before, but something… changed…? I think… I changed, or… or you changed, or… something changed… something… good…”

“Good baby sis…” Yeji kissed between Xinyi’s eyes, and smiled as she felt Xinyi’s thighs clench tighter around her own. “Something did change, but that’s fine. Things change all the time. The only constant is change, isn’t it?”

Xinyi stared up at Yeji once her eyes could focus, an adorably confused expression fighting against one that was more purely aroused than anything else. “Uhhhh… do they…?” She blinked slowly, her large eyes looking all the more youthful and empty than they had before her orgasm. It was as though she’d came away more of her maturity, more of her wisdom, and left herself that much more unable to be anything except Yeji’s little sister—mostly because that was exactly what happened. “Is… it…?”

Yeji laughed, kissing between her little sister’s eyes again and again as she made adorably giggly sounds between each press of those soft, warm lips. The cold woman who had been fervently confident she would win if she took the initiative had completely forgotten about the promotion and her competition with Yeji.

She remembered the way Yeji’s thigh felt against her pussy, and the way it felt for her big sister to claw her back or squeeze her ass, or giggle as she twirled in short skirts that flipped up to show even tinier panties. Those things felt much more important than being smart, or important, or well-paid. Yeji would always take care of her anyway. That was what sisters did for each other—big sisters, anyway. Xinyi knew she was too simple, too much giggly eye candy to provide any real help for Yeji.

The least she could do was warm her bed and offer her body as a plaything.

“Yes, Xinyi. It’s an expression, but I guess your mind isn’t really good at holding on to things like that. Not anymore.” Yeji kissed between her eyes, and Xinyi squealed as her eyes crossed again and her whole body wiggled. “You are… just too cute. How do you feel, then, about me taking over for you? I can think for you, I can tug you to bed, help you dress…”

“Would I get to think even less?!” Xinyi’s eyes grew wide, looking larger than they already did. “I’d just get to be a good little sister and do what you told me to do…?”

Even though they had just been discussing that very concept, Yeji’s mind had already let the memory drift away. Caught up in the sexy feeling of her big sister’s embrace and the simple, all-consuming euphoria of knowing they would be together forever it was hard to focus on much else.

Remembering things that happened a minute ago was simply too complicated and she didn’t feel like she had any time for it at all.

“That’s right, Xinyi.” Yeji purred, a single finger lifting Xinyi’s chin. Forehead pressed to forehead. The moment their eyes met, Xinyi mewled and fell completely limp. Her mouth hung open, waiting on any little thing Yeji might say to do. “I can take control of everything and all you’ll ever have to do again is be my sexy, obedient little sister. I thought this might take longer, but… why wait? Why don’t we take the last steps now?”

Xinyi’s heart beat faster, harder, desperately in her chest. Her thighs clenched. Her whole body writhed. I want it, I want that, so much, but why… why do I feel like I should say no, like I should struggle, like…

She struggled against the hazy fog that filled her mind more and more thickly as of late. It took being smart and clever to get to where she was in life, but she felt anything but when she was home, when she was with Yeji.

Even at work she’d been wearing the same short skirts, the same dipping tops, the frilly, lacy underwear that so many had been able to glimpse with the ways she couldn’t stop herself from moving. She wasn’t offering herself, or flirting with anyone, anyone but Yeji, but that didn’t mean she wasn’t putting herself on display while thinking so much less than ever before.

Didn’t I… some kind of… scholarship…? Smart…? Xinyi wrinkled up her nose, whimpering and shaking her head. For some reason, banishing that thought made her nipples throb. That sounds so… hard… I don’t wanna… Want my big sis to think for me…!

Giggling made Xinyi’s clit throb, and she liked that. She liked grinding into her sister’s thigh, clenching her own as she giggled just to feel more stimulation. She liked being thoughtless and sexy. She liked how it felt to know that sometimes when she walked down a hallway at work, now eschewing lab coats unless absolutely required, plenty of people were able to see so much of her ass as her own movement swept up her skirt.

The idea made Xinyi so hot she couldn’t stop grinding against Yeji’s thigh. Doing that quickly made her devolve into desperate pants, her eyes hooded, her mouth hanging open as she groaned.

Nothing outside of Yeji’s thigh felt like it mattered. She knew that if something else was important then Xinyi could take care of it. She knew that whatever happened, she was safe with her big sister.

Better than that, she had her big sister’s wonderful leg grinding against her.

“Well, my cute little baby sister?” Yeji purred, nails teasing down along the backs of her sister’s thighs before they slid back up to grasp both sides of her ass at once. Xinyi squealed, arching back dramatically. “What do you say? Do you want it, sis?”

“Wh-what were you offering… me… again…?” Xinyi’s words were punctuated by moans, pitiful soft sounds that themselves were half giggles. “I can’t… remember… so… hot… wanna rub… wanna… cum…!”

Yeji laughed, squeezing her sister’s ass tighter and tighter until Xinyi squealed even louder. “You just came, Xinyi.”

“I… I did…?” Xinyi blinked, but she was so disoriented, her body so burning with lust, that her right eye blinked before the left. “Don’t remember… that… either… just feel all sticky-hot… needy ‘n… don’t wanna… don’t wanna think… wanna… fuck…? Wanna fuck you wanna… wanna be fucked by you… wanna… wanna… ohhhh…!”

Xinyi cried out, shuddering as she trembled against Yeji. Drool teased its way down from the corner of her lips, and her head fell back. The only part of her eyes that could be seen was white.

“So you want me to think for you, to take control, to help you enjoy yourself instead of worrying about a job or anything silly like that…? Just doing what I tell you to do…?” Yeji smiled, grasping Xinyi’s hair to make her forehead once again brush her own. “And answer quickly, or my dumb little bimbo of a sister will forget what I asked her all over again…”

“Answer… quick…! Uhm… okay… like… do I… want… that… mmmmnnn…!” Xinji whined, pressing her breasts into her sister’s body with more strength, more roughness even as she lost her grasp. Her hands were twitching too much, too weakened by the pleasure and lust that drove her forward. “Y-yeah… that means… means you make me feel good, and I… I just do… do what you… nnn… will I… will I get to cum again if I say yes…? Will you… fuck m e…?”

Yeji grinned.

“Of course I’ll fuck you, my sexy little sister. You’ll cum so much, and it will feel so good each and every time.”

“Then yessss…! Yes…! Do the thing…!” A mess of giggles and moans, Xinyi couldn’t keep her body still any more than she could properly direct it. The fog in her mind was more present than anything even vaguely resembling thoughts. “Take me…!”

Yeji purred, fingers sliding up along her little sister’s body until they slowed and moved tenderly along Xinyi’s face before sliding back down. The lower they moved, the softer and more distant Xinyi’s moans and giggles sounded. All of the volume drained away, as did all of the strength in her hips. No longer able to do anything but melt into the bed, Xinyi moaned as the second pass of Yeji’s hand drained away everything else.

Xinyi’s eyes melted shut, and her involuntary moans were the most pitiful sound she’d made yet.

“Good girl, Xinyi… Very good girl.” Yeji purred, her hands pulling back to instead stroke along her ‘sister’s’ hair, and then down along her back. “You’ve been so good for me, getting dumber and dumber, simpler, hornier… needing me to take the reigns of your mind, to guide you, to be responsible because you’re not enough of a person to do that for yourself… which is, of course, exactly what you always wanted our relationship to be…”

“Always… wanted…” Xinyi moaned, soft and pitiful, as her whole body shook and clenched. “Y-yesss…”

“That’s right… always. I’m giving you what you’ve always wanted, that’s why you’re going to do something very important for me, tomorrow…” Lips melted between her eyes again, and Xinyi groaned. “You’re going to help me get the most important promotion of my life, and then you won’t ever need to work again. You belong in my bed… mmm maybe under my desk… I’m sure you have the skills to be a certain kind of secretary… just not the kind anyone else but me even knows is there. How does that sound…?”

“D-don’t know…” Xinyi groaned. “Too… stupid to know… Xinyi needs… Yeji to tell her… what she thinks… Needs Yeji to tell her… Everything…”

Yeji shuddered, her eyes hooding low. It was the glance of a predator, but all of the warmth in her eyes made it clear that she wasn’t about to make her now obedient roommate’s life miserable. She might have robbed her free will, but all she wanted from here was to make things better for both of them.

Financially and sexually gratifying for Yeji.

Mindless and euphoric for Xinyi.

“Then it sounds good, because I said it does…” Yeji purred. “Doesn’t it…?”

“S-sounds… good… it’s… good…!” Xinyi groaned. Processing her big sister’s commands was the most complicated thing she could still do.

“Melt for me, Xinyi…” A single finger stroked down along Xinyi’s nose before tapping the very tip as though it were a button. Xinyi moaned, her every breath shuddering through her body in ways that made her round body arch against Yeji. “Melt, and let the last of your intellect simply fade away. You can let me take care of everything… and tomorrow, we can go into work with you dressed like the sexy young thing you are for me, the dumb little thing you are for me… and you can meet our new playmate.”

Xinyi moaned, her head trying to move in something resembling a nod but lacking the strength.

“Melt… and obey.” Yeji kissed between her eyes, and Xinyi moaned.

“O-obey…”

When Xinyi would awake the next morning, she wouldn’t remember anything that happened but she would care less than she ever had before. Her big sister took care of things like that.

All she had to do was be a good, obedient little sister.

That was the way she liked it.