Her younger sister, Lina

"Hi Stace!" came the chipper voice over the speaker. "Um, promise you won't be mad, but I got sent home from school today. It wasn't even a big deal, I just weirded out Mrs. Prudeface. I'll tell you about it when I get home - please don't freak out, 'kay? Love you!"

Stacy blinked, her own unpleasant morning temporarily eclipsed by her frustration at her younger sister's antics. This wasn't the first time she'd "weirded out" the teachers at school, why couldn't she just skip classes like everyone else.

She'd barely checked the time the message was left when she heard the front door opening.

Lina walked into the kitchen, dumping her backpack on the floor before raising her hands comically in front of her face.

"Stace! Are you h- oh shit, Stace! Put some clothes on!"

Stacy blushed furiously, running to her room and throwing on an oversized shirt before going back into the kitchen. Lina had dumped a lot of her uniform on the floor and was fanning herself over a glass of juice, her shirt half-undone.

"Shit, Lina. Put some clothes on." Stacy said pointedly, getting a snort in response.

"It's hot. Uniforms are dumb. Besides, you're one to talk."

Stacy stole a sip of juice to get Lina's attention.

"So what did you do this time?"

Lina scowled defensively. "Hey, it's not my fault Prudy McBumface doesn't mind her own business. What I do with my sketchbook is my own business and if she wants to stick her face in it without my permission, then she can get a face-full of what I do and like it."

Said sketchbook was already on the table and Lina slid it across to Stacy with a sullen look.

"Viewer discretion is advised," she said with evil sarcasm.

Stacy opened to a random page. Oh, dear.

It wasn't uncommon for high school kids to do the "rebel" thing and draw violent nonsense or fill their books with what they thought was revolutionary anarchistic bullshit. Compared to what Lina spent her spare time on, that was practically normal.

Stacy turned a page. Yes, she could see why any teacher, or member of the public would be a little disturbed by what they saw. Any decent member of the public.

Smut wasn't the half of it. Not by a long shot. Stacy wasn't sure a lot of the positions depicted were physically possible and knew for certain that some of the anatomical combinations were entirely fictitious. Lina wasn't a bad artist, either - that was the problem. The realism of the drawings was part of what made them so shocking. Stacy was surprised Lina hadn't been arrested.

Her eye was drawn to a particular image on one page, one that - compared to the others - was fairly tame but at the same time opened a pit in her stomach: A slim woman, reclining on a deck chair, her back arched, her face frozen in a paroxysm of ecstasy as the cock that rose from her loins sprayed a fountain of cum into the air.

Stacy marveled at the detail, how Lina's pencilwork managed to emulate the play of light against the woman's glistening skin, her expression of delight mixed with a hint of confusion, as though her body were beyond her own control...

Stacy felt her heart beat faster as the image grew in her mind, and was beginning to go a little weak at the knees when the book was suddenly wrenched from her fingers. Lina shut it under one arm, wearing an intensely awkward expression.

"Hey, don't stare," she said, her face bright red. "It's weird, I get it. You don't have to ham it up."

Stacy wanted to say that weird didn't cover it. Wanted to say that Lina was wasting her life. Wanted to say that she needed to keep that stuff in her pan- at home. But her heart was racing now, her mind flooded with the images of naked figures writhing against one another, all of them enraptured and enthralled, drowning in sex.

A shiver ran through Stacy's body as she felt something between her legs harden, sliding out of her pussy and dripping with slime.

Lina didn't notice, her worried face focused on Stacy's hungry expression.

"Stace? Quit it. You're weirding me out."

Stacy's legs took an unsteady step forward, her nipples hard against the fabric of her shirt. She hadn't willed it, but couldn't think through the fog of arousal.

Lina shrank back, but would have to turn away to slide out of her chair and was transfixed by the sight of her sister's predatory gaze.

"Stace, you're scaring me. Please, I'm sorry, okay?"

Stacy's body lurched forward, causing Lina to fall backwards onto the floor with a scream. Stacy's arm made a grab for her, catching a handful of her skirt which came free and slid down her legs. Lina kicked herself free, standing to run but Stacy's body was already on its feet, lunging at her again, their combined momentum carrying them into the living room.

Stacy was shocked out of her fugue when Lina's elbow caught her on the jaw, but her body was completely unfazed, grabbing wildly as Lina struggled. Stacy tried to regain control of herself, to somehow help Lina escape and find someone to stop her, but her body paid her no heed.

Lina's shirt popped open as the few buttons holding it closed came free and bounced across the carpet, her panties twisting this way and that as they were wrenched forcefully down her legs. Eventually she was pinned to the floor, naked, exhausted and helpless with Stacy's panting body over her.

I'm sorry, Stacy tried to say. It's not me! It's not me doing this!

Lina lay exposed and still fighting beneath her, silent tears trickling down her face. Stacy saw something catch Lina's eye below them and saw her eyes widen in shock as she stopped struggling. The throbbing sensation between her legs told her exactly what it was that Lina had seen.

"Oh my God," Lina breathed. "Oh my God. Holy shit. Holy shit."

Stacy and Lina locked eyes, and where she had expected to see horror or fear, Stacy saw an excited fascination in her sister's gaze. As though surrendering herself, Lina spread her legs below Stacy's body and exposed her neck in supplication, her breathing becoming shallow as she panted.

"Be gentle."

Stacy felt her own horror overcome by the sensation of something in her body snapping, the sudden rush of lust consuming her from the waist up. Her head was **** down into the crook of her sister's neck, running her tongue lovingly along it, causing Lina to moan out loud. Stacy's body repositioned its legs, lowering its hips until she felt the head of her cock nuzzle the already dripping entrance to her younger sister's womb.

Oh God, no!

As though in acknowledgement of Lina's request, Stacy's body thrust forward slowly, tenderly parting Lina's pussy lips as it snuggled its way into her body. Lina's back arched, her eyes closing as she moaned again, wincing when Stacy felt her cock meet a wall of resistance and break it.

Stacy wanted to be sick, wanted to feel sick, to feel anything other than the intense pleasure of having her cock wrapped in the tight folds of her sister's virgin pussy. But all she could do was drown in bliss as her body began to pump itself in and out of the nubile figure that writhed beneath it, mewling in tortured ecstasy.

Lina no longer needed to be restrained, and she raised her arms around Stacy's neck, pulling herself up for a kiss. Stacy felt her tongue come to life, diving into Lina's mouth as they made out like...

Horny high school kids, Stacy managed to think. It's like a dream come true. I'm a college student fucking a catholic high school chick.

The thought brought another spike of pleasure into her thrusts, plunging herself into her sister who moaned as the breath was **** from her lungs. Stacy lost herself as she felt her world reduced to nothing but the joy of physical sensations. The pussy milking her cock, the young body cradled in her arms, the soft mouth moaning against her lips.

Stacy had completely forgotten that she'd lost control of her body, wanting to fuck her sister as badly as the creature that had turned itself into her cock and they came together as on, Stacy's cock erupting while her pussy trembled with an indirect orgasm.

Lina broke off the kiss, her eyes screwed shut as she seemed to savour the sensation of cum - her sister's cum - flowing into her. Stacy's body held Lina close as she squirmed in her embrace, her breath coming out in gasps and sobs.

Lina cried out in protest and Stacy realised as her cock shrank back into her body that she could move again. She shot up away from Lina but her sister grabbed her, pulling her down again.

"Stay inside me," she panted. "That was amazing!"

Stacy internally recoiled at how quickly her sister had accepted being ****, how willing she was to be fucked by her puppeteered sister. She couldn't have known, but despite that Stacy still felt a little betrayed.

Stacy extracted herself from her sister's grasp, peeling their sticky bodies apart as Lina reluctantly let her go. Already, cum was dripping from Lina's slit onto the carpet and cried out in distress as she tried to press it back into herself. Disgusted, Stacy dragged her into the shower where Lina spent most of her time stroking herself with a faraway expression. Stacy washed, dried and dressed - properly, this time - before heading back to the kitchen for... she didn't know what. She just couldn't stand to see Lina massaging her cum against her slit.

She was half asleep in her chair when she felt arms reach around from behind and hug her tightly.

"Hey, why so quiet?" Lina said, pressing their cheeks together. "I wasn't that bad, was I?"

Stacy pushed her away, and she sat down on the opposite side of the table with a look of concern.

"What's wrong? I'm on the pill, so it's fine, right? You're clean, aren't you?"

"And that's all you're worried about!?" Stacy exploded. "You've just been fucked by your sister's dick and you don't think that's a bit strange?"

Lina rocked back. "Hey, I'm surprised but it's not like it's the end of the world." She grinned. "It's actually super cool."

Stacy stared. "How can you say that?"

"Well, I mean it's amazing that you've kept it hidden for so long. Does Alex know? How did he react?"

"He doesn't know," Stacy hissed. "Nobody knows."

Lina's brow furrowed. "What? Not even mum and dad?"

"I haven't always had it," Stacy said through clenched teeth. "It... I got a package in the mail. There was a thing inside that bit me, latched onto my... latched onto me. It originally looked like a grey worm but it... stole my blood and turned into a cock."

"No way," Lina breathed, her eyes alight with excitement. "Is it a part of you? Can you control it?"

"No." Stacy's voice was bitter. "It... It controls me."

The silence lasted far too long for Stacy as she tried to read her sister's expression.

"So, what you're saying," Lina said slowly. "Is that when you pushed me down..."

"Yes," Stacy said, hoping to cut off the rest of the question.

"...and slid your cock into me..."

"Yes."

"...and fucked my brains out..." Lina's voice had become hoarse with disbelief.

"YES."

"...you were being controlled by your cock?"

Stacy stared at the kitchen table, saying nothing.