The Erotic Mind-Control Story Archive

Story: Hypnotizing my Big Sis to be my Fuck Doll, Book One

Codes: mm in sf mf

Ned lacks self-esteem. His successful, supermodel big sister has undermined him all his life. When Ned’s favorite science teacher leaves him a sunbed reprogrammed to alter the human body, his size-zero sister insists on a tan and Ned turns her into the chunky fuck doll of his dreams. Saskia screams blue murder but she’s going to have to submit to Ned’s demands if she wants her supermodel body back.

HYPNOTIZING MY BIG SIS TO BE MY FUCK DOLL, BOOK ONE

It’s no wonder I’ve come to dread the journey home from school. Every afternoon, at the school gates I have to run the gauntlet of the three witches. The three smoking hot witches.

Dolores Smith.

Sammi Duarte.

And Hazel Winterbourne.

“Oo! Here comes hunky Ned!”

“Oh my God! Ned’s so-ooo spunky!”

“What a dude!”

It’s bad enough being taunted mercilessly every single afternoon. What makes it even worse is being taunted every single afternoon by such drop dead gorgeous chicks.

Dolores Smith is svelte and slinky! She’s got such dark, sultry eyes!

Sammi Cortez is so chunky and curvaceous my cock starts to ache just looking at her!

Hazel Winterbourne takes blonde bombshell to a whole new level!

As I approach, Sammi crows:

“Oo-ooo, Ne-eeed. Dolores fancies you! Dolores thinks you’re so-ooooooo hot!”

They all fall about laughing.

Dolores screams at the shocking accusation.

Fancy that doink? I do not so!”

“Yes she does!” shrieks Hazel. “Dolores is dying to go out on a date with you, Ned!”

They caw and cackle like a flock of parakeets.

Dolores jabs her finger down her throat and makes vomiting noises to indicate how the idea of going out on a date with me makes her feel.

Me? It’s Sammi’s got the hots for you Ned. It’s Sammi wants you to ask her for a date!”

“Oo-ooooooooo! Dolores! You bitch!”

I walk past them as fast as I can. What makes their mockery unbearable is the fact that I’d give my right arm to date Sammi Duarte. I’d give a million dollars to be Hazel’s or Dolores’ boyfriend, but there’s no chance of that ever happening in a million years.

I climb into my beaten-up Volvo and head for home.

Their teasing hurts, all the way back to my house.

I park outside, and before I get out of the car I check my face in the rear view mirror.

I don’t know what’s wrong with me.

Technically speaking, I’m quite good looking. If my face weren’t so permanently burning with doubt and embarrassment I might even be called handsome. I’m six foot one and I have a comparatively ripped physique. I ought to be attractive to girls. I’m not built to be a laughing stock, but here I am, the number one dweeb in my class, the helpless butt of the three witch’s mockery.

I can’t work it out. It has to be something psychological. There must be something not right in my mental makeup that makes me such a failure with girls. I’ve got some bigger problem in my life that’s crippling everything I do, particularly my attempts to find a girlfriend.

Another glance in the rear view mirror and I know at once what my bigger problem is. I know immediately the cause of my romantic difficulties.

Saskia.

My older sister.

My big sis, Saskia.

My stuck-up, snobby, bossy, older sister, successful fashion model and all round self-appointed superstar. Twenty-one years old and her career already a meteoric success where mine’s a total car crash. Saskia’s just back from a successful swimwear shoot in California. She’s just won a new contract with a leading Milan designer and it’s making her even more unbearable.

Life can be cruel.

I hate to admit it, but my sister does have what it takes to be a successful model.

Tall. Slim. A svelte figure. The sort of toned ass and bud-like breasts Milan designers favor. Wavy black hair. Flared nostrils, retroussé nose. Cupid’s-bow lips. Dark, lustrous eyes. Saskia’s one hundred percent photogenic. It’s a pity no one ever sees her horrible personality.

When I get in she’s stretched out on the couch in the living room issuing orders to my Mom about how to cook a pot roast.

“Cook it at a higher temperature! It’s not braising quickly enough!”

My Mom cooks the best pot roast in town but my big sis, who’s never boiled an egg in her life, is suddenly a cordon bleu instructress.

She sneers the minute I come in.

“Oh! You! Mister Straight A-s!”

Her sarcasm stings. Everyone knows I got straight F-s, for FAIL. She doesn’t have to rub it in.

My big sis looks me up and down:

“Hey! Dude…” Her ‘dude’ drips sarcasm. “Scored any hot chicks lately?”

I mumble:

“Piss off, Saskia.”

She knows I never score any hot chicks.

She sneers down at me from the height of her fashion model hauteur:

“Bet all those girls in your school are just droo-oooling over my spunky little brother!”

I mutter:

“Leave me alone.”

Yes. My sister’s the cause of all my problems. Saskia’s the root cause of all my problems in general, and of my problems with girls in particular. She’s three years older than me. Saskia’s always done her best to put me down. She never stops undermining my morale. Ever since I was little my big sister’s always been there shooting me down at every opportunity. She never misses a chance to sap my confidence and destroy my self-belief. She became particularly mean and nasty when I started getting interested in girls. And since I turned eighteen my big sis’s contempt has been full-on, in my face, unbearable.

Her laughter turns to a sneer:

Leave you alone? I bet those girls just can’t leave my smoking hot bro alone!”

She’s worse than Dolores and Sammi and Hazel put together.

By the time I get to my bedroom I feel completely destroyed and humiliated. It’s my sister who’s the cause of all my problems. Dolores and Sammi and Hazel might be vicious little witches, but they’re just skirmishers for my big sis’s occupying army and…

… Worst of all…

… There’s not a goddamned thing I can do about it…

* * *

Next day, at school, my science teacher calls me into his office. I’m due for another dressing down. I’m about to have a few more strips torn off me for my shockingly bad results.

“What is it, Ned…?” Strangely, old Mister McCrory’s face seems concerned more than angry. “… What’s the matter? Why can’t you concentrate on your lessons…?”

Concentrate…?” I like Mister McCrory. I try to keep the sarcasm out of my voice but it’s impossible. “… With all the girls tormenting me… and my big sister around?… you try concentrating with my big sister around all the time…!”

His already wrinkled forehead wrinkles some more.

“Big sister, ey? Oh. Right. I see… you’ve got big sister problems…”

“You bet I have.”

I fill him in on a few of the gory details.

Mister McCrory pushes his pebble-lensed glass higher up his nose. He says:

“Yes. But, Ned! You’re a bright boy. You’re my best student by far, even if you end up getting straight F-s. Don’t let it get to you.”

He’s right about me being his best student. I love science, particularly physics. I’ve taught myself a lot about electronics and quantum mechanics. There’s nothing I don’t know about the wave function, but it all gets messed up in exams.

My bitterness wells up. I blurt:

“Don’t let it get to me…?… you don’t know what my big sister’s like…!”

I tell him about how Saskia’s undermined my confidence ever since I was little, how now that I’m eighteen she’s particularly undermining my confidence with girls.

“With girls, ey…” Mister McCrory runs his fingers through his wispy white hair. He sucks his dentures in: “… I’ve always had problems with… erm… girls… erm… myself…”

Everyone knows that Mister McCrory is a confirmed bachelor. It looks like I’m going to end up a confirmed bachelor myself.

He strokes the stubble on his chin:

“… Yes, Ned… I had a big sister too… just like yours… she totally screwed up my life…”

I believe him. Mister McCrory has the ravaged face and watery, sorrowful eyes behind his thick-lensed glasses, of a man whose life has been totally destroyed by another. It’s horrible to think I’m going to end up that way myself.

I mumble:

“… Yeah… well… there’s nothing you can do about it now, sir…”

Mister McCrory’s sixty five. He’s due for retirement any day.

He firms his chin. He thrusts his chest out. Mister McCrory readjusts his glasses:

“Nothing? Nothing I can do about it? I’m not so sure about that, Ned. I’m not so sure about that at all. Come with me, lad. You’re coming home with me. I want to show you this little invention I’ve come up with in my spare time.”

* * *

Half an hour later I’m standing in a chaotically untidy apartment in front of a sunbed.

Books piled up on the chairs. Dishes piled up in the sink. It’s hard to believe a professional teacher could live in the midst of such chaos.

I stare at Mister McCrory’s invention:

“A sunbed?”

That’s what it says on the side of the long glass tube with the upholstery inside.

MegaSun K7. DeLuxe Sunbed.

Mister McCrory has the palest, most papery skin I’ve ever seen.

My teacher chortles:

“No. Not a sunbed, Ned. A converted sunbed. A sunbed programmed for higher purposes!”

“For higher purposes? What higher purposes?”

He coughs a little, then clears his throat:

“… To… erm… remodel the female… erm… body… and mind to a more… erm… satisfactory state…”

“Programmed?”

“You heard me!” He nods at a bank of computers attached by a wilderness of cables to the sunbed. “This machine isn’t for anything as pathetic as getting a tan!”

He opens the lid of the sunbed. He pokes his head in, explaining how his machine works.

In place of ultra-violet bulbs for emitting a deep tan into pale skin, an array of feelers have been fitted into the electrical sockets. Mister McCrory switches on the power and fern-like fronds come flexing down from the roof of the sunbed and massaging in from both sides, giving off a spooky light even more powerful than UV. Anyone lucky enough, or unlucky enough, to be lying stretched out on the upholstery would he having every inch of their body caressed by the feelers.

The old teacher runs his fingers through his hair:

“Ultra Violet Tactile Enhancement! UVTE!” He readjusts his glasses. “It can touch any part of the recumbent body when the lid’s closed. Head. Hair. Stomach. Spine. Bottom. Knees, back or front. Calves ditto. Feet. Soles. Toe tips. Every part of the human body can be reached and enhanced!”

Enhanced…?

The word sounds somehow scary.

He shrugs.

“Yeah… well… transformed… you know, improved… !… micro-sensors in the feelers read all the current data and dimensions of the… erm… subject’s body… and transmit new data and dimensions—the data and dimensions required by the… erm… operator—back into the recumbent body so that it grows into… grows pretty quickly, if I do say so myself… into the… erm, shape and form and bodily structure required by the operator…”

“Improved? Transformed?”

It sounds more than scary.

“… Mm-mmmmmmm… that’s right… the machine doesn’t actually change the subject’s mind of course… no, certainly not… the brain is naturally out of bounds… but it can alter the subject’s… erm... feelings, especially her feelings for the operator… particularly those feelings housed in the… erm… lower organs… you know… love, liking, sexual desire… that sort of thing… perfect for your sister…”

I nearly jump out of my skin.

“My sister?”

“… That’s right, your big sis… this machine can alter your sister any way you want… big breasts, small breasts… large bottom, small… it can even make her like you… “

Like me? I thought you said it didn’t reach the brain.”

“… Yes… well… not all liking resides in the brain, Ned… you ought to know enough biology by now to know that…”

The more he describes the sunbed’s salient features the more ominous the MegaSun K7 looks.

I hold his eye:

“And all these alterations the machine does to the subject’s body… they’re reversible…?”

“… Reversible…?” For a second Mister McCory looks confused, like he’s never heard the word before. “… You mean… change back into the original body state and sexual appetite…?” His gaze wanders. “… Oh… yes… yes… yes of course… anything in nature can change back into its original form…” He doesn’t sound too sure. “… The machine records all the subject’s information holographically. If you want to undo an… erm… unfortunate alteration, just type the original codes back into the computer and Bob’s your uncle…” He isn’t all that convincing. “… Breasts… bottom… those hour-glass hips… all… shipshape…”

“You mean it only works on women? Not on men? You’re saying that Ultra Violet Tactile Enhancement only works on females? Not men?”

The old man chuckles, back on safe territory:

“… No… no… not at all… the UVTE works on males just as effectively as it does on females…” He holds the lid open. “… In you get…!”

My scalp prickles.

“… Me… ?”

I gesture at the open sunbed.

“… In there…?”

“… Yes… in you hop… what would you like to alter… biceps…?… abs…?… cock…?

I back away.

“… No… no… I’m… my body’s fine thank you…”

Mister McCrory nods at my crotch. He chuckles.

“What about that penis of yours, Ned… fancy something a bit longer…?”

I stare down at the hotted-up sunbed.

“… No… no… no I don’t… it’s okay as it is, thank you…”

He snaps his fingers.

“… C’m on… snip snap… you’ll be amazed…”

His eyes go big and stare-y. His glasses twitch and wobble. He’s insane but then…

He’s my teacher

… He’s taught me everything I know about science…

I pull my T-shirt off over my head. I climb out of my jeans.

“Boxers too!”

I reluctantly take my shorts off.

Mister McCrory frowns at my cock.

“Oh my days. You shouldn’t be having trouble scoring with a thing like that between your legs, young man.” He’s right. I am pretty well endowed. Much good has it done me. He grins. “How long would you say it is, Ned? Twelve? Thirteen inches. Non-erect, of course?”

“… How long… ?… hell, Mister McCrory… I don’t know, do I…?”

He produces a ruler.

“… Better measure you then… make a proper experimental study, what… ?… show you the UVTE gets results, ey…”

My science teacher’s measuring my cock. He stretches it out to its full length on his palm and wrist and takes a measurement.

“… Mm-mmm… yes… thirteen inches… just as I expected… unlucky number, but not for the young ladies, ey…?” He nods at the machine. “… In you get!”

The school gates flash before me. Giggles. Laughter. Guffaws:

‘Oo! Her comes hunky Ned!’

The three witches at the school gate. The three smoking hot witches.

‘Dolores fancies you, Ned. Dolores thinks you’re so-ooooooo hot!’

The mocking tones of the biggest witch of all.

‘… Hey… dude… scored any hot chicks lately…?’

My big sis. My leering, jeering, sarky, insufferable big sister, putting me down more and more, the older and more desperate I get.

‘… Leave you alone? I bet the girls can’t leave my smoking hot bro alone, ey…?”

I climb into the machine. I lie down on my back looking up at the UVTE fronds in the underside of the lid. The upholstery is surprisingly comfortable.

I murmur:

“… Hey… what’s that music…?”

Space-y music starts coming out of speakers set into the top end of the sunbed somewhere above my head. The music has an immediate lulling effect on my anxiety.

Mister McCrory chuckles:

“… That… ?… oh that’s to hypnotize you…” The music’s hypnotizing me already! “… One’s better off unconscious whilst undergoing a major bodily transformation…”

I want to get straight back out of the sunbed, but my brain suddenly feels all dreamy and my limbs are no longer obeying instructions.

Mister McCrory puts a pillow under my head. He covers my face with a rubber mask.

He chuckles:

“… Best not experiment on the face, ey… ?” He smiles. “… You don’t know what you’ll end up with…”

He shuts the lid.

I hear a click.

The machine begins to pulse and whir.

I feel somehow more than hypnotized. The effect is immediate and powerful, on my mind as well as on my body. A lulling darkness overwhelms me from head to toe. Fronds of ecstatic light—the machine certainly feels good— play over my cock, and work more gently over the other parts of my body too. If this is hypnosis it sure feels good. I’d quite happily let the undulating darkness go on forever…

… But after about five minutes the whirring stops, the fronds with draw, the lights go out, I hear the lid being drawn back and the mask is removed from my face…

“Hey! Mister McCrory! That’s real cool!”

The machine’s switched off but I still feel blissfully trippy.

Mister McCrory’s watery eyes aren’t concerned with how cool the sensation was. His wizened frown doesn’t care about my blissfully trippy state. He’s got my cock in his hand, and his ruler out measuring.

“… Mm-mmm… just as I thought… a perfect result, ey…?… have a look… see for yourself… fourteen inches…!

I check and double check the measurement. I can’t believe it. There’s no denying. My penis has grown a full extra inch. My thing feels considerably thicker too.

Mister McCrory reassures me that when it comes to size the machine works in both directions.

“… If you want to hop back in I can get you back down to thirteen again…”

My face burns.

“… No… no… never mind… it’s alright… fourteen’s my lucky number…”

He beams triumphantly:

“… Just think of the results you can reap on a woman’s body, Ned…!… on your sister’s body… your big sis will be putty in your hands… her fashion-model body will be putty in your hands… you can change her into anything you, or she, wants…!”

“Yeah but…”

His machine might be at the cutting edge of bio-computer technology… it’s still totally useless…

I blurt:

Saskia will still hate me! She’ll still loathes me! My big sis will still despise me! The machine will never change that!”

Mister McCrory chuckles complacently:

“… Oh well… you’re right there, Ned… if your sister despises you there’s nothing we can do about that…”

I realize that my science teacher is mad. Not just dotty. Not merely eccentric. Mister McCrory is clinically insane. His machine’s diabolical. The whole concept behind it is fiendish, a devilish breaking of the laws of nature. Who does Mister McCrory think he is? God? Master of the Universe? Albert Einstein? He’s nothing but a frustrated teacher at retirement age meddling in things that shouldn’t be meddled with.

It’s lucky the sunbed and attached computers are so bulky. Mister McCory wants to give me his invention. He says that, with its help, he solved his own problems with his own big sister, but luckily the apparatus is too cumbersome for me to take home, even in my beaten-up Volvo.

However, a week later a shocking thing happens.

It’s announced at assembly that Mister McCory is dead. The old science teacher passed away peacefully in his sleep after a long day teaching quantum mechanics.

So that’s that.

The following Monday a truck turns up at our house. I open the front door for the delivery men. My Mom and Dad and big sister are all out. The men carry the UVTE machine through to my bedroom.

Mister McCrory’s left it to me in his will.

* * *

I’m in my bedroom still trying to work out how I’m going to get the UVTE machine out of the house before my parents find it, when my big sis walks in.

It’s one of Saskia’s many nasty habits that she feels she has the right to come cruising into my bedroom at any time of night or day to pass comments or deliver another put-down.

She stares at Mister McCrory’s invention.

“Oo! What’s my little brother gone and got himself here?”

She’s in her usual skin-tight black jeans and strapless tube top that show off her size zero figure. Today her cupid’s-bow lips are a glossy shade of damson to match her damson nails. The effect should be witch-y, but with her stunning face all Saskia looks is sensational.

She looks at the MegaSun7 Deluxe and attached computers. She sneers:

“Oo-ooo! Tanning are we? My little bro thinks a nice deep tan’s going to improve his chances with the girls?”

I mutter:

“… No… no I don’t think that… I just…” In fact I’m pretty well-tanned already. I’ve got a nice beach-hunk complexion. It’s done me no good whatsoever. “… I’m just… you know… looking after it for someone…”

Someone, ey?”

My big sister sashays over for a closer look. Even ‘relaxing’ at home Saskia never fails to move with a catwalk hauteur. She pouts:

“Oo! A MegaSun K7. DeLuxe! Your ‘someone’s got plenty of money then! MegaSun K7’s top of the range!”

My sister knows everything there is to know about skin-deep beauty.

She frowns. Her eyes light up:

“… Act-uuu-aaaaaally…” Her plump lips moue. “… I’ve got a swimwear shoot tomorrow… Hunza G…”

She looks her arm up and down. Her arm is slim and perfectly toned. She pouts:

“… I co-ouuuuuuuld do with being a touch browner… Hunza G suits dark tans… I am a shade light…

She smiles at the machine.

“… How about I have twenty minutes in your MegaSun, Ned? Darken up a bit…?”

She lifts the sunbed’s lid! She peeps inside! She doesn’t even ask!

I cry:

“… No… no way… sorry… impossible… it’s broken… there’s no power…”

Saskia smiles:

“Don’t be silly…”

She’s already seen the LED lights glowing and the live computer screen where I’ve plugged the contraption in.

“… It’s perfect…!… thirty minutes…!… give me half an hour…!”

She’s taking off her clothes!

My big sis is peeling her jeans down over her petite, supermodel’s ass. She’s treading her panties into the floor.

She pulls her tube top off over her head.

Her small, taut breasts slip free of elasticated lurex.

I cry out:

“… No… no… you can’t… it’s… it’s not ready yet…”

She ignores me. She ignores me like she’s always ignored everything I’ve ever said.

She climbs into the sunbed. She lies down flat on her back. I’d always guessed my big sister shaved her pussy, I just didn’t realize how stunning a shaved pussy could be.

“… Okay, maestro…” She puts on the mask. “… Maybe an hour at… let’s see… Caribbean setting… alright?”

She adjusts the mask and lies back. The mask covers her whole face, even her eyes, especially her eyes. She can’t see that the MegaSun bulbs have been replaced with UVTE feelers.

She snaps:

“… Go on… what are you waiting for…?”

I close the lid.

I don’t know what to do. Perhaps I should just turn the machine off, let her lie there for an hour, pretend she’s getting tanned.

No. That’s no good. My big sis knows sunbeds. She’ll realize I’m deceiving her.

Perhaps there’s a standard tanning setting I can use.

What did she say she wanted, ‘Caribbean’?

I go to the computer screen Mister McCrory’s wired up to the sunbed.

A perfectly-formed, three-dimensional, holographic image of my naked sister floats in the center of the screen.

I touch the mouse.

There’s a humming noise. The machine springs into action.

Even from the outside I can hear the gentle rustling whirl of Mister McCrory’s feelers descending on my big sis’s recumbent body.

I wait for her to start screaming and shouting and banging.

Nothing.

I look down through the lid. The multitude of Ultra Violet Tactile Enhancers are at work, feeling their way across my sister’s body, reading her pneumatic data, recording her figure formation, registering every pore of her silky skin.

Saskia’s stretched out perfectly at ease, toes touching, ankles together, calves drawn in, her thighs pressed together, hips relaxed, stomach spread out tranquilly, her dainty breasts rising and falling. She’s one hundred percent hypnotized.

I remember the powerful effect the apparatus had on my mind as well as on my body, when I was lying under the feelers, the lulling darkness overwhelming me from head to toe, the undulating blackness of the machine’s soothing caress. My big sis is clearly enjoying the same full body experience.

I turn to the computer. Her hologram body looks even more beautiful too, floating in 3D in the screen, a computerized specimen of voluptuous female perfection drifting in the binary void, surrounded by grid lines and vectors, wave function axes and Feynman curves.

I touch the mouse.

A curved vector swoops. The vector makes contact with the computer-generated image of my big sister’s size zero breasts.

They’re not size zero any more!

The vector hovers over first one computer-generated tit and then the other computer-generated tit. The hologram’s bud-like breasts begin to swell.

I glance into the sunbed. I look down at where my sister’s lying.

My hair stands on end.

I stop breathing altogether.

My sister’s real breasts are swelling too! Her small compact tits are already twice their original size!

They look better than they did before. Fuller. More toned. Far more alluring. Softer but shapelier too.

My scalp prickles. I twitch the mouse, draw the vector away from the magnificent pair of breasts.

I’ve just altered my sister’s body.

Improved it. Made it even more beautiful…

… Well… beauty’s in the eye of beholder… beauty’s only a matter of taste and personal preference…

I personally prefer Saskia’s larger breasts to her former size zero ones. It’s not a crime to prefer one size over another. Everybody has their own particular kink…

… Her nipples look so much cuter, more pink and taut and tingly standing up erect on so much curvaceous fullness…

… Other people may prefer size zero… fashion photographers and swimwear designers… Saskia herself may prefer size zero… it’s not up to her… it’s up to me…

I return the vector curve to the hologram’s curves and add a fraction more fullness to the breasts, some extra steepness to the cleavage.

… Yes…

… Much better…

… A wonderful feeling of ease and power takes hold of me…

I take the mouse and apply some wave function axes to the expanse of my sister’s belly. I draw it a fraction wider and longer to make up for the extra weight of the breasts.

Down in the sunbed, my sister’s belly extends.

I hold my breath. I stop breathing altogether and add some extra meatiness to her winged hips, to go with her new breasts and belly… when you’re altering someone’s body you need to keep things in proportion…

Down in the sunbed, my sister’s winged hips grow fuller, deliciously heavier.

Right on cue— my sister’s a sunbed aficionado—Saskia rolls over onto her belly.

Her butt is so perfect it’s a shame to be even thinking about modifications. Two taut, toned ass-cheeks, beautifully tanned, her rear cleft breathtakingly tight.

I move the Feynman curves in and add a little weight. I feel like a criminal, a cool, calm and collected criminal. I redefine my sister’s exquisite ass-cheeks. I prefer a little more weight in a bottom myself.

Inside the sunbed, Saskia’s butt swells to new levels of perfection.

It’s done. I’m finished.

I shut my eyes and pray to God my sister likes her new body. She’s sure to approve. She’ll see at once how a brother’s discerning eye has canceled every slight imperfection and made her body even more desirable than it was before.

I glance at my watch. Her hour’s up.

I switch off the machine.

Saskia rolls over and takes off the mask.

My big sister climbs out of the sunbed and takes a look in the mirror.

“… Ee-eeeeeeeeeeeeeeeeeeeeeeeeeeeeck…!

She rounds on me:

… What’ve you done, you bastard…?

“… Nothing… I just…”

… What have you done to my freaking body…?

“… You… you… look great…”

She cups her new, wobbly tits in both hands, feels how heavy they are. She stares at her new, taller nipples. She gazes aghast at her new chunky hips. She spins round and studies her butt’s new curvaceous fullness.

… Great… ?… I look freaking hideous…!… I’m a… I’m a… I’M FAT… !”… She starts screaming: “… I’M A FAT UGLY SLOB…!

How can she say such a thing? She looks sensational. Her new, chunky body suits her. She’s far more beautiful than she was before. My heart’s racing madly, just gazing at her new, drop-dead-gorgeous body. My stomach’s suddenly all churned up. I feel a tingly weight in my cock, just looking at a big sister I’ve never known before.

… What have you done…?” She kicks the machine. Her fist punches at the sunbed glass. “… What have you gone and freaking done to me…?

I try to explain. I tell her about my science teacher, Mister McCrory, about how he died and left me his invention. How the MegaSun7 isn’t really a sunbed, it’s a machine for changing peoples’ bodies. I explain that the machine’s made her body much nicer than it was before.

… Much nicer…?” She flies completely off the handle. “… Much nicer, you freaking doink…?

I mumble:

“… You’re beautiful…!”

She is too. The extra weight suits her. She’s far more curvaceous than before. He breasts are toned and succulently shapely. I want to take them in my mouth, taste their sumptuous softness, one at a time, clasp her perky nipple between my teeth. Her ass is sensationally rounded. I want to cup both cheeks in my hands, feel her voluptuous fullness quake in the palms of my hands. She even feels like a much nicer person. Warm and generous and big-hearted. A far more attractive human being, matching the unchanged loveliness of her face.

I remember what Mister McCrory said about the UVTE machine changing the subject’s feelings, especially her feelings for the operator, particularly those feelings housed in the lower organs, such as love, liking, sexual desire. Could it be that Saskia may even come to like me?

She screams:

… Oh go-oood… !… GREAT…!… I’ve got a freaking shoot tomorrow… my Hunza G swimwear shoot…!” She runs her fingers frantically through her lustrous wavy black hair. “… I’ll be the laughing stock of the fashion industry… none of the swimwear will fit…!… my career…!… my future…it… it’s all down the drain…!

My heart’s beating violently. She’s so beautiful. My big sis is sensational. The tingling weight in my cock is getting heavier and heavier. I shrug:

“There’s more important things than swimwear shoots, babe.”

… No there isn’t… !… what are you talking about…?” She nods frantically at the machine. “… Does this thing go into reverse… can you change me back to how I was before…?

“… Erm…”

Mister McCrory did say how the machine could change its subject’s body back to its original form. He did mention how the UVTE micro-sensors recorded all the subject’s original data and dimensions and saved all the details of their original form and bodily structure, in case of an, erm, unfortunate alteration. He did believe that the subject’s body could be returned to its original state— ‘pore-perfect’ was how he put it—if so required.

I look at her. I say:

“… Yeah… yeah… of course it can change you back… if you want…”

She shrieks:

I want!

I shrug:

“… Yeah… but… how are you going to say thank you to your little bro for saving your career…?”

She stares dumbly:

Thank you?

It’s like she’s never heard the words before.

I unzip my pants:

“… You heard me… ‘thank you’…”

I step out of my jeans. I tread my shorts into the carpet. I let her see how big and heavy my cock is, the full fourteen inches aching between my legs.

Her jaw drops open. Her eyes go big and wide:

“… You want me to…?”

It all comes flooding back. All the years of insults and mockery. ‘… Hey! Dude…” her ‘dude’ dripping sarcasm. ‘… Scored any hot chicks lately…?’ It all comes flooding back. How she’s always done her best to put me down. How she’s never missed an opportunity in my whole life to undermine my self esteem. How her sarcasm’s become particularly poisonous when I started to get interested in girls. How she’s worse than Dolores Smith and Sammi Duarte and Hazel Winterbourne put together. ‘… Bet all those girls in your school are just droo-oooling over my spunky little brother… !’

I say:

“That’s right, babe. I want you to.”

My big sis looks particularly lovely when she’s startled, her mouth wide open with shock, the succulent lips that have spent eighteen years putting me down, preparing to take my throbbing spear-head.

She stares, wide-eyed:

“… But… but… I’m you’re sister…”

“… DU-UUUH…. I know that, don’t I…?… I aint that dumb, sis…”

“… But… but… you’re my brother…”

She keeps stating the obvious.

I shrug:

“… So…?”

I offer her my cock. My full length is already starting to thicken out. I grin:

“… Why don’t you have a feel, doll… if you want to go back to your original shape, that is…”

She bristles:

“… You… you can’t do that…!… it’s… it’s blackmail…!”

I laugh:

“… Try me… you can either suck my cock… or turn up for your shoot tomorrow with those cute N cup tits and that bootylicious butt…”

She stares down at the voluptuous fullness wobbling her chest, the naked, meaty curves quaking her sensational ass.

“… I’ll… I’ll tell Mom and Dad… I’ll go to the police…”

I shrug.

“… Go on… tell ’em… tell the cops too… you’ll be sixty pounds heavier for the rest of your life…”

She looks at me with big, yearning doe eyes:

“… You promise you’ll change me back…?”

“… Cross my heart and hope to die…”

She reaches out. Her palm closes tentatively round my cock. Her fingers feel warm and supple, registering the big weight stiffening in her hand.

I take a deep breath. I say:

“… Feels good, ey…?”

She hisses:

“… You bastard…”

I murmur:

“… Just keep pumping, babe… you know how to do it…”

My sister’s only twenty-one but she’s already dated a movie star and a senatorial candidate.

Her palm tightens round my aching shaft, squeezes a few voluptuous spasms into my throbbing gristle, begins to pump slowly up and down, gathering all my pounding weight into her hand. She feels the full weight of my imperious need to fuck her stiffen and spring upright in her hot fist and pumps a little faster.

I run my fingers through her hair:

“… Feels good ey, baby…?”

“… You cunt…!”

‘Cunt’s a new one. Usually it’s just ‘doink’ and ‘dweeb’. She can call me ‘cunt’ as much as she wants, I can tell from the warm friction of her hot fist slipping up and down my rock-hard shaft that my big sis hasn’t sucked sixteen inches before.

I murmur:

“… You gonna suck that for me, babe…?”

“… Fuck off…!”

She’s always been arrogant. She’s always had a mind of her own.

Her tongue-tip flirts with my piss slit. A kitten’s tongue-tip darts at the aching slit in my rock-hard spear-head’s drumming tightness, savors some tangy pre-cum, licks and flutters and probes for the big load building up in my balls.

She draws her mouth back.

“… You promise you can change me back completely…?”

I massage her scalp through her hair, guide her mouth back onto my pulsing spear-head.

“… Completely, babe…”

She takes my swollen tip between her teeth. Succulent incisors sink into rock-hard throbbing, clasp my aching tip in a luscious love-bite.

“… Argh… argh…”

Her tongue plasters my spear-head in succulent saliva, mixes her throat’s warm gag with the urgent pre-cum squeezing from my cock’s pounding tip. She likes how I taste. My big sis approves of my tangy pre-cum. She hoovers it into the back of her throat with long, voluptuous sucks.

“… Argh… argh… argh-llllllllllllll…”

She cups my balls in both hands. She massages my rocks, never once stopping sucking at my aching tip. I don’t ask her to massage my balls. I don’t request that she squeezes my rocks. She just does, freely and of her own accord. She squeezes nice and hard. She balances the full weight of the pulsing load I’m going to give her in two warm palms and lets her fingertips wander playfully through my bush, squeeze my throbbing rocks through their tight sacs.

“… Glurg… gla-aaaaaaarg…”

It’s the first time a girl’s ever sucked my cock. I’ve no way of making comparisons but I get the feeling my big sis does it real good. In fact she’s probably an expert. The sixteen inches of rock-hard shaft between her softly mouthing lips and her warm palms clenching and unclenching round my balls feels ready to explode.

“… Argh… argh… argh-lllllllllllllllllllll…”

I want the sensation to go on and on. It feels too good to ever stop, except the explosion keeps on building up.

“… Glurg… gla-aaaaaaaarg… argh-lllllllllllllllllllll…”

The guys at school say getting your cock deep throated is the best feeling ever… my big sister must be an expert… unless she’s deliberately tormenting me… lavishing tongue love on my throbbing spear-head, massaging my balls, making the other sixteen inches wait.

“… Argh… argh… argh-llllllllllllllllllllllllllll…!”

I take her tits in both hands. She’s crazy ever wanting to reduce them, to even dreaming of shrinking them back to size zero. She’s insane wanting her flat, boyish chest back.

My sister’s voluptuous fullness quakes in my hands. I squeeze, and a flutter of heartbeats spasms her luscious tits. Hot, tight nipples gouge my palms. She’s insane ever wanting to change back. These full, wobbly breasts suit the generous racing of her heart.

“… Argh… argh…”

Her teeth let go of my spear-head’s slippery ridge, slide down and clamp my throbbing shaft, and keep on sliding, down and down, combing ecstatic shivers from my pulsing stake, down and down and down, needing to get my full length in her luscious wind-pipe, desperate to house my full sixteen inches in her gullet and choke herself on my aching tip.

“… Argh… argh… argh-llllllllllllllllllllllllllll…!”

Fu-uuuuuuuuuck!

My heart stops beating.

My jaw drops.

My eyes go big with amazement.

“… Glu-uuurg… gla-aaaaaaarg… argh-llllllllllllllllllllllllllll…!”

My big sister’s cumming! Her hand’s between her legs, a fingertip slithering wildly, three fingers pumping knuckle-deep into a sumptuous wetness.

Her tail-bone kicks. Her butt quakes. Her pussy jerks and bucks, riding on a surge of sudden ecstasy, going over the brink, impaling her throat again and again, gullet-deep on my throbbing spear-head!

“… Glu-uuuuuuurg… gla-aaaaaaaaaaaaaarg… argh-llllllllllllllllllllllllllll…!”

My big sister chokes and splutters. She gags on my big cock, bringing herself off with her fingers, not caring whether she breathes again or not.

“… Argh… argh…”

She draws her mouth away, gasping and panting, strings of gag and spittle stretching from her moist, swollen lips to my swollen tip like a glistening suspension bridge.

Her smile’s all goofy, gag and pre-cum running down her chin:

“… Gonna cum in my mouth, big boy…?” Big boy? She’s never called me ‘big boy’ before. “… Wanta jack off down my throat, big fella…?”

My sister has always been so prim and proper and uptight. I’ve never heard her use such language before. She doesn’t even mention changing back to her original shape. She’s forgotten all about her former figure too. I don’t even have to make any promises. Her only demand is that I cum in her luscious mouth!

I groan:

“… Yeah… I’m gonna jack off down your throat…”

Maybe her high-class boyfriends have taught her special skills…

… Or maybe it just comes naturally to my big sis…

… She forms her mouth into a juicy O, her lips a succulent jujube stretching itself wide open and yearning…

… She opens wide for the dentist and drops her gullet swift and sure down sixteen inches of rock-hard cock…

“… Argh… argh… argh… argh…”

… She impales her luscious throat on my throbbing spear-head again and again and again…

A rush of ecstasy comes flooding up my cock.

I grab her hair. I grab two handfuls of silky luster and ram her mouth up and down on my pounding piston, faster and faster, in time to the sweet pulsing of her throat.

“… Glurg… gla-aaaaaaaaaaaaaarg…”

Her wind-pipe fills with succulent throat honey. She gargles my throbbing spear-head in pulsing spittle and voluptuous gag.

“… Argh…”

The jolt goes through the both of us. My cock jams in hot, slippery wind-pipe. I run my fingers through her silky hair and pump surge after surge of hot cum down my big sister’s sumptuous throat.

“… Gla-aaaaaaaaaaaaaaaaaaaaaaaaaaaarg…!”

She finally lifts her mouth away. Gag and spittle, mixed with hot throbbing cum, overflow her lips and stream down her chin and abseil onto the beautiful new breasts I’ve given her.

She coughs. She clears her throat. She splutters:

… Okay, you bastard… had your fun…?

Had my fun? She had fun too, I’m sure of it. I definitely felt her cum at least twice, maybe even three times!

… Finished have you now, you moron…?

In the blink of an eye she’s back to her old mean, nasty self again.

I want to blurt out ‘… you enjoyed it too…!’ but no words leave my mouth.

She struggles to her feet.

… You better freaking change me back, you moron…!

Moron? What’s she talking about, ‘moron’?

I grab my phone off the nightstand.

She lurches against me, her body still twitching post-climax.

I grab her around the waist. I force my head against her head. I raise my phone and take a couple of quick selfies, just in case. Just in case of what, I’m not exactly sure, but the mood my sister’s in, I need some insurance.

She climbs back into the machine cussing me out.

… I don’t want to be one micro-millimeter different from how I was before… you hear me…?

She puts the mask back on and lies down flat on her back on the upholstery, seething.

… A hair out of place and I’ll freaking kill you…

I can’t remember whether Mister McCrory said the that UVTE feelers altered the subject’s hair or not.

I close the lid.

I turn to the computer.

Her chunky body floats in holographic perfection on the screen, hanging in a net of grid lines and vectors and wave function axes and Feynman curves.

I try to remember where I stored her original body data, her shape, form and bodily structure’s original dimensions.

It’s in here somewhere.

Columns of figures. Spread-sheet sized arrays of numbers. Terabytes of binary options.

Mister McCrory never actually demonstrated the UVTE machine’s reverse procedure.

I should have let him try it out on my penis, after he enlarged it. Vanity stopped me double checking whether the machine has a reverse procedure at all.

I remember the uncertainty in his voice:

… Reversible…? like he’d never heard the word before.

‘… you mean change back into the original body state and sexual appetite…?’

If anything, my old teacher had shown a blasé lack of interest in reversing ‘unfortunate alterations’.

‘… Oh yes… yes… yes of course… anything in nature can change back into its original form…” He hadn’t sounded too sure.

The screen fills with algebraic formulae and asymptotes to infinity.

Yes.

I think this is it.

The page with my big sister’s original body data saved on it.

I click OPEN.

The hologram body floating on the screen condenses. The 3D figure suspended on computer blackness draws in its breasts, shrinks its nipples. The stomach contracts. The curvaceous butt tightens.

I hold my breath:

The legs grow slimmer. The arms are no longer muscular.

A bleeper bleeps.

A light flashes on and off.

The light is green.

I shut my eyes and hold my breath. I aim my eyes at the depths of the sunbed and open them.

A perfect, size-zero, supermodel-level body lies dead still on the upholstery. The slim legs and pert butt and small, bud-like breasts are perfect for the catwalk in every way. Saskia has regained her real body. My big sis has recaptured the body she was born with. The chunky curves that meant so much to me have melted back into the minimal ones that Saskia prefers.

She sits up and pulls the mask off her face. Wavy black hair. Flared nostrils, retroussé nose. Cupid’s-bow lips. Dark, lustrous eyes. One hundred percent photogenic. Yes, it’s Saskia again.

I close my eyes. I wait for the shouting and yelling and cussing.

“… Mm-mmmmmmm… that was so-ooo relaxing, bro…”

Bro? She’s never called me ‘bro’ before.

A warm body rubs against me.

I open my eyes.

My big sister’s size-zero fashion-model body is rubbing softly against me.

Her taut, tight nipples graze my chest. Her bud-like breasts firm themselves against my pounding pecs. Her shaved pussy nestles against my suddenly aching cock. Her lips brush succulent moisture over mine.

“… That’s the best hour in a sunbed I’ve ever spent, Ned… I’ll have to do it more often…”

She’s hypnotized. My big sister is still under hypnosis. Her body’s returned to its former state, but her mind’s remained in its mesmerized trance.

She sways against me. Her knuckles lightly graze my cock, feel it starting to stiffen again.

“… What setting did you use… Caribbean…?… or Mediterranean…?”

Saskia’s in a hypnotic trance.

She’s forgotten that she sucked my cock. She thinks she’s just had an hour in an ordinary sunbed. She has no recollection of the big load I shot down her throat.

I say:

“… Caribbean…”

My sister’s body has returned to normal, but her mind has changed utterly. She has a whole new personality.

I can see it in her eyes—the blissed-out, trippy trance. The lulling darkness overwhelming her from head to toe. She’d quite happily have let the undulating darkness go on forever. It’s the way I felt, blissful and hypnotized, when Mister McCrory finished demonstrating on my penis…

… Which means…

Maybe I’m still hypnotized myself!