The classroom lab is silent. The cleaner came by about a minute after the bell rang, emptied the bins and left. Now, it's just me and the stack of books I'm marking, pen scratching the surface as I cross something out, leave a comment or award merits. Or not. Apparently, Dylan thinks electrostatic charge is caused by the electrons hating each other. Close, buddy, but nil point.

I absent-mindedly rake one hand through my frizzy blonde mane, sigh, close his book and open the next. At least Olivia’s reasoning is coherent.

Electricity is one of my favourite topics to teach, and the kids get a kick out of it. Especially when we experiment with the Van de Graaff generator. It helps that the new teaching assistant is hot. Usually they're all ginger beards, man buns and hemp shirts they seemingly wash once a decade.

But not Rob. He’s nerdy, sure. Wears awful shirts like his mum still dresses him. But I can overlook fashion sense when he has enough stubble that I know is going scuff just right between my thighs. And soulful brown eyes that I want staring up at me while he does it.

Crushing on the hired help isn't my usual style, and I mark another book as penance. But thoughts drift back to him. How I get butterflies when we brush skin. How his soft Scottish baritone makes me shiver. I'd probably get wet if he recited Planck's constant to seven significant figures.

It's pathetic really. Theoretical physics is dry. No wonder nobody learns it. Practical science has become less of a thing with today's health and safety bureaucracy, but I like to eschew guidelines every so often. Demonstrate principles whenever I can. It helps cement learning.

No experiment is more fun than zapping a bunch of kids. It sounds horrific when said out loud, but they love it and never forget how electrons flow. We did it today, after the obligatory demonstration of me standing on a plastic step, placing my palm on the silver dome and switching the generator on. My long hair rose and spread until it resembled a fuzzy halo. It caused a stir.

I explained the reasons for the electrons being stripped off the metal comb in the base, onto the moving insulated belt of the device, and dumping the positive charge at the top, spreading it across the dome. Then how it's transferred to me, where the charges repel one another and try to escape from my split ends.

After powering it down and discharging the device, the fat spark arcing to the grounding wand, I addressed the class:

“Okay, who wants to find out how electricity flows? I warn you: it will sting.”

A few eager hands flew up at first. The usual early adopters who would volunteer for a box unboxing. Then a few more who didn't want to be left out.

“Perfect. Anyone with piercings or metal braces, over there.” I point to the corner. “You're on the observation deck to explain what's going to happen. The rest of you, grab a plastic step, stand on it and form a chain around the class. Make sure you're not touching anything other than the hands of your neighbour.”

They arrange themselves, threading between the desks, amid a hubbub I have to shout over. “I need two extra brave volunteers.”

Fearless Freddie, of course.

“Come on then, Freddie, you're at the head and get to touch the generator. Who else? Karl? Perfect.”

Karl's a gobshite and a bit of a bully, so his role is fitting.

With the help of my dreamy teaching assistant, we arrange the chain and check there are no earth leaks, and everyone's on a step. Freddie's palm is on the dome and I ask the observation deck crowd what's going to happen when I switch the machine on.

Various answers fly back until we settle on… nothing, because they're all insulated. I flick the switch and the noisy machine whirrs. It gradually charges the chain. There are giggles as hair rises and they all tingle with the flooding charge.

“Now then,” I turn to the observation deck, “What will happen if someone touches earth? Shall we find out?”

Of course, there's a chorus of yesses. Slightly less enthusiastic from the human chain. “Karl? Fist bump Aisha please.”

He steps up to the last girl, they dap, and instantly the members of the chain all shriek or yell, and jerk free of one another, giggling as a few hundred thousand volts, and a tiny current, zips through them to reach Karl's shoes.

It's a fun experiment. No doubt I'll get at least one complaint from a horrified parent tomorrow when one of the kids excitedly babbles over dinner, “Miss Barnes electrocuted us today.”

The pile of books is never-ending. But I know if I take them home, I'll just look at them and do something better. Like, ooh, run a bath, climb in and luxuriate in the suds. Trace my hands over my slippery skin and pretend it's Rob. Whisper his name as the water sloshes and I brush, then pinch, my sensitive nipples. Trail fingertips down between my legs. Glide them against the soft skin. Decide it needs to be softer, grab my razor and make short work of removing every trace of hair. So his stubble has free reign to scuff when his tongue swoops up through the delicate folds.

Dirty thoughts would whirl as he eyes me with an earnest intensity. Laps at my pussy like I'm a saucer of milk. Brings me to the cusp of orgasm then backs off the licking until it's mere whispers, fluttering my eager nub as I writhe and beg for it harder. The gradual increase in tempo and intensity will have me gasping, grappling for the back of his head to clutch him to my wetness. Throw my head back, arch, and moan as I spill into his mouth.

I jolt in my seat. Withdraw my hand from my undies, blushing even though nobody is around. My fingers glisten and I lick them clean. Fuck, what am I doing, masturbating at work? What's wrong with me? I rearrange myself. Wiggle on the chair. I'm wet. I can feel my lips sliding together, knickers damp beneath the far too sensible skirt.

Such an ache. It's distracting to the point I can barely focus on the scrawl in the books. I have to cum. Fast. Hard. But what can accelerate the climax? If I carry on touching myself at the desk it'll take time and the caretaker will want to lock up soon.

I flick my attention around the room. Maybe the desk corner will do the trick? Hike my skirt, tug my panties aside and crush my clit to the wood as I pinch and squeeze my nipples? They're sensitive and I adore playing with them. Always makes me cum.

Always. As does my favourite home accessory: the nipple clamps, bought online last year. Love that anticipation right before securing them, the sting registering as the jaws bite and I roll my head, tugging the chain between them to tent and deform the flesh. Maybe the crocodile clips at both ends of the electrical flying lead on the bench would do as a surrogate? Those teeth piercing the caps, sending sparks through my breasts from the vice-like contact points as I tug the wire between them?

Yes. I reach for the lead. Pause.

Sparks.

My attention lands on the Van de Graaff generator. A shiver ripples through me. Could I? Would it work? A frisson of excitement stirs. My pussy drips into my panties.

Fuck.

The chair scrapes when I stand and round the bench. I face the machine. Size it up. Too high. But the tables behind me are much lower. I slide the heavy contraption towards me, hoist it in my arms, shuffle over and carefully place it on the closest desk. The power cable still reaches the sockets on the bench. More importantly, the dome is now roughly chest height.

The full body shudder grips me. Should I? Is it safe? A tabloid article flashes through my mind.

A Shocking Boob

Local schoolteacher Madeleine Barnes, 26, was found dead at St Mary’s High School, slumped over a piece of apparatus used to generate millions of volts. She'd been using the Van de Graaff generator after hours to stimulate her breasts with sparks…

No! It's safe enough. They exaggerate. It's only a few hundred k-volts. If I'm earthed and touching the device when it’s switched on, there's no potential drop. Same as if I had my hand on it. But as I move away, the air will ionise and the charge has to go somewhere. The path of least resistance to Earth.

Through me.

Fuck it. I'm desperate.

With shaking hands, I unbutton my cream blouse enough that I can access my breasts. Scoop them out of the bra and lean forward, pressing them to the freezing surface of the metal dome. They complain. Stand on end. It's delicious. Decadent.

Reaching down to the base, I put my finger on the switch. Breathe in.

Wait. Fuck! The underwire. Close call, Maddy. Stepping back, I unhook the bra and wrestle myself free of it, pulling it through the armhole of the blouse and dumping it on my bag out of harm's way.

I also kick off my flats, bare feet on the floor, step in and press my tits to the dome once more.

With a final mental and physical check there's no metal nearby, I reach down. Inhale. And throw the switch.

The motor cuts through the quiet. I pray the caretaker is the other end of the school.

As predicted by theory, nothing happens. I have the same potential as the device accumulating charge that flows from the dome to Earth. Net neutral.

The moment of truth.

Apprehension builds and I thumb the switch, almost bottling it. Hold my breath. Pull away from the surface a couple of millimetres.

The reaction is instant, like the chain in the earlier experiment. Tiny sparks zap from the dome to my hovering nipples. No pattern to it, just randomly picking one or the other and discharging through them.

I gasp. “Fuck!”

Each little snap releases a flash of pain, and the unpredictability of which breast is going to be shocked next has me mewling into the quiet classroom in no time.

I mash my chest to the dome when the sensation overwhelms me, and the sparks cease. I breathe hard, almost panting. My knickers are soaked. But I haven't cum.

Lifting my hand from covering the off switch, I slip it under my skirt. Beneath the fabric of my panties too. Brush my clit and chew my lip.

Starting slow circles, I pull away from the device and the blue sparks resume, the noisy belt continually topping up the charge, crackling my nipples a few times a second as physics tries to reach equilibrium.

I mumble. “Yes, Rob, bite them. Make them sting. Mmm yeah. Harder.”

Increasing the distance another couple of millimetres, the rate of sparking slows. But my god the power goes up. I almost scream as the electricity snaps across the gap.

“Fuck yes, bite them hard.”

My fingertip circles faster. More insistent. I jolt each time the surge picks a nipple to discharge through. Pull back a little further, slowing the rate and doubling the intensity. No, inverse square law… quadrupling it? I can barely think straight, a sustained moan escaping as the cracks of mini lightning singe my hard nipples.

The orgasm rises, fingertip rapidly working my pearl, tits aflame with bursts of pain that ebbs into pleasure.

The arcs leap an inch, maybe two, now only every second or so, but the thump as each discharges is too much to bear. I cry out, tensing, thoughts tumbling, “Fuck, Rob, yesss.”

The climax grips and I flop against the rumbling device to ride out the ripples. Echoes of the shocks continue to radiate through me and I'm unable to move as the power of the orgasm clutches at my frame. Swear I can detect burning flesh, but it's probably my imagination.

As the ripples fade, a grin spreads. Fuck that's intense. Fast. But if anything, too fast. I'm still ravenously horny.

Plucking my fingers free, I fumble at the desk until I reach the switch, power it off and wait a few seconds for it to discharge fully through me. Stand shakily. Eye the device. Pondering. Size it up.

I wonder.

Hiking my skirt, I thumb the panties down and step free, depositing the ruined scrap of fabric on the desk. The gusset is dark with juices.

The need has barely dented. I know I have another in me and will probably implode if I don't address it before I get home.

I cup my tits. Squeeze them. Pinch the nipples and they respond, begging for more. The flying lead beckons. I grab it. Open the jaws of one end, steel myself and ease them shut over the stiff teat.

Holy fucking mother of death, it stings. I groan as the blood flow is stymied but it seems to divert juices to my pussy. Moreso when I attach the other and tentatively tug the cable between them, my breasts lifting and dropping.

Time is very much against me now. If I don't cum soon, I'll probably pass out.

Clambering onto the desk, I straddle the dome. If it gets wet, I guess it'll be less effective because the surface will leach more charge. So I can't touch it, but I can probably control the arcing by opening and closing my thighs. When clamping the dome between them, nothing will happen.

It might just work.

It's precarious. Another headline flashes through my head.

Pleasure Dome Claims Life

Local schoolteacher Madeleine Barnes, 26, was found dead at St Mary’s High School, neck broken after falling from a desk while riding a piece of apparatus used to generate millions of volts…

I've no idea what's wrong with me. My libido's been off the charts recently, but this is insane. All I can focus on is the rush. The need. My tits throb. My cunt aches for attention. I'm a mess.

Adjusting my position so I can reach the switch, I grip the sphere between my legs, reflection distorted in its silvery surface, and flick the lever with my big toe.

The device rumbles. Charges. Taking a deep breath, I gingerly release the dome… and nothing happens besides the continued tingle as strands of hair levitate.

My brain steps through the process. Gah. Of course. I'm insulated on the table. I could earth myself somehow. Or move the generator to the floor. Probably safer, too.

Flicking it off, I climb down, hump the apparatus to the floor—the cable just stretches—position myself over it and fire it up.

As I part my legs I'm not ready for the reaction. Sparks leap to the closest surface connected to ground; my inner thighs, randomly alternating left and right legs.

“Aahhh-ohhh. Fuck.”

Instinctively I spread them further but the sparks intensify until I’m squatting low enough that the discharge point shifts. The closest surface is directly above the dome. My cunt receives a colossal bolt due to the distance and I scream. Then another. And another. Clutching for the desk edge to steady myself, I lower so the zaps speed up but lessen.

The sensation is out of this world. Sparks rocket across the gap, lighting up every erogenous zone in my body at once. I risk holding the desk with one hand and zero the fingers of the other on my clit, mashing it and gasping as the barrage of shocks mount. 

My imagination takes over and I chant under my breath, “Oh, Rob, that’s it. Lick me. Bite me. Fuck yesss, make it hurt.”

And in my mind, he does. Teeth nipping my cunt lips. Breath short and sharp as I drip onto his chin and cheeks. His hands grip my arse to pull me to his eager mouth, to devour and mistreat my wayward pussy.

I lift a tiny distance, the shocks thickening. “Fuck! FUCK!”

My knuckles whiten where I grip, fingertips mashing my clit in rough circles. “Gonna cum, gonna cum fuck fuck fuck yes YES!”

As my body spasms for a second time, my hips rock, the distance changes and the bolts intensify. I scream, let go of my clit and stand sharply, almost losing my balance.

Heat and pleasure become one. My tits feel as if they're going to explode. As the incredible waves of orgasm batter my body, I scrabble at my chest, tugging the lead and groaning as it sways, only serving to distend the flesh until I grip one, squeeze to release, and relief floods in.

My orgasm peaks again, lengthened by the sensation of the blood surging into my starved nipple, and thick gasps fill the room. It's the singular most exquisite experience in my life.

Until I fumble the clip in my hand.

It falls.

At the extent of its travel, it swings like a pendulum.

And brushes the charged dome.

A couple of hundred thousand volts stab my nipple and I shriek. The orgasm reignites, pulsing, and I clutch at the clip, detaching it, slumping against the bench to ride out the high, a gasping, wet wreck, and flinging the cable away.

It skids across the floor to stop at the feet of the open-mouthed caretaker in the doorway. I don't even notice him at first, the cataclysmic waves still thumping through my body, but as the seismic fog lifts, I double-take, hand flying to my mouth. I scramble to stand and tuck my tits away.

“Uhh, Graham, shit, I can… uuhh, it's not what it look… well, okay, it probably is what it looks like, but I can still explain.”

He bends to pick up the flying lead. Sways it to and fro, a grin spreading. “I always wondered what the science department did after hours.”

I eye him, black polo shirt, jeans, boots, my adrenaline spiking. “I didn't mean to… it's not us. Things just sort of… snowballed, oh god this is embarrassing.” I swipe my soaked panties off the desk and hide them behind my back. Flick the rumble of the machine off with my toe.

As the room deadens to nothing, he brings his gaze ever so slowly up my body to stare. “Who's Rob?”