V struggles at first, testing the position in which I've placed her, something she always does despite never yet finding a way out of her bindings and despite both of us knowing she doesn't really want to escape.

Soon she settles a little, though still fidgeting as the cold steel of the bar draws the heat from her thighs and chilling her clit deeply. I watch, taking in the delicious sight of her exposed and vulnerable in the cool air of the night.

She's on her tiptoes, with much of her weight on the scaffolding bar that runs between her legs. V has always liked to hump, so I know she's quite comfortable. Or not in excessive pain, at least.

Her arms are pulled above her head, the chain of the cuffs stretched over another bar, and her eyes are covered by a black silk blindfold. The rest of her body is exposed to our surroundings, though no-one overlooks us here in the neighbour's garden.

Our neighbours had got fed up of their ongoing extension project so had taken off to Greece for a week, and of course we agreed to keep an eye on the place, feed the cat, etc. Also, their garden was more private, so we could have some filthy fun.

I'd got home a little early, and saw the builders off after they'd packed everything away for the weekend. One of them in particular had caught V's eye, and I'd encouraged her to masturbate to the thought of him while listening to them work outside the window. She'd been delighted to oblige my suggestion, of course.

With a little preparation I had everything set up for V's return from work. I wrapped the crotch-height scaffolding bar in a few layers of clingfilm, and dampened the ends of the bar with insulation so the vibration wouldn't alert the rest of our neighbours to our little adventure.

The moment she got home I was on her, not that that would be in any way unusual. I stripped her quickly, pulling off her trainers and jeans, her little white socks and her white top. While taking a moment to kiss her deeply and appreciate her pale green frilly lace lingerie, I enjoy her eager kisses in return, and hesitate before removing the last of her clothes. As spectacular as she looks in her underwear, I want her to feel completely exposed tonight.

V is always eager to please, and when in a submissive mood there's no brattiness at all. So it's with ease that I blindfold her and lead her outside, though she blushes when I instruct her and guide her to straddle the bar, and moans as the cold steel pushes into her hot, puffy lips and presses hard against her delicate clit.

She humps the bar immediately, and doesn't resist as I lift her arms and cuff them high above her head. She's helpless and completely in my power now, and I step back to watch that realisation take hold.

She squirms, moans deeply and whispers, "Who's watching me?"

I quietly come close, lick the edge of her ear and whisper back, "You'll never know for sure…" as she squirms and humps and squeaks in excitement. "Stay right there while I grab a few things from the house."

I don't rush, confident in the privacy of the neighbour's garden and the quietness of the are in general. She'll be on high alert for any slight noise or movement around her, but the only likely disturbance is a curious cat.

I return perhaps 3 or 4 minutes later, quietly moving in the twilight. She hasn't moved (naturally) but her freckled skin is now covered in goosebumps. Unsure whether it's a combination of excitement or the cold, I immediately decide to make her shiver.

I press one finger at the nape of her neck, then slowly and deliberately run it down her spine. She starts like she's been shocked by a cattle prod, humping and stamping her feet, twisting and trying to pull at her cuffs, and a little shriek escapes her lips. I grin at the power of my touch.

I move closer and kiss her deeply, and her response is urgent and needy. Her tongue feels hyperactive, greedily seeking mine and swirling around my mouth. I have her total focus and attention now, she's hungry for my slightest touch. Exactly what we both need after a stressful few days.

I enjoy her kiss for a little longer, then pull back and press her ring gag between her teeth. It's large, purchased by her to be the perfect size to fit my thick cock so I can facefuck her when I have her tied up. She's very thoughtful that way.

She often struggles with the jaw stretch at first, but I caress her cheek as she gets accustomed, and soon she's as comfortable with it as she's going to get. She's about to be distracted anyway.

Her next adornment is a pair of nipple clamps, the clover ones that test her limits when used in isolation, but I intend to overwhelm her with sensation this evening so they'll be half forgotten in a few minutes.

I clip them on, and I'm rewarded with a stifled moan and the first strings of drool overflowing her lips. I know she has a love/hate relationship with that feeling, so I make the most of it and whisper in her ear, "You messy slut, you look sloppy and filthy dribbling down yourself."

These are powerful words for a woman so used to being perfectly presented and always in control of herself. She humps and bucks against the cold steel in response. I lick a line of saliva off her breast, and step back to admire her. She's the perfect fucktoy.

Perfect she may be, but if I leave her too long the cold will numb her clit beyond possibility of orgasm, and that would be frustrating for us both. I plug her most powerful wand into the extension cable I prepared earlier and clamp it firmly to the bar as close as I can to her clit without touching. It might just transmit enough vibration through the metal to do the job, especially as she's mounted so firmly on the frame. I don't turn it on yet though, I want the vibrations to come as a surprise when they do.

I run my finger down her spine again, and slap her pale cheeks hard, once each side. A distinct pink handprint rises immediately on each one as she groans and drools and pulls on her cuffs.

She's close to subspace, but not quite there. The riding crop will get her there, I think. It's our nastiest one, and my favourite. Just under a metre long, and with a stiff, narrow tip. It will soon bring some warmth into her skin, and push away any lingering thoughts of work or the wider world.

The first impact is on her left arse cheek, and she flinches hard, then moans at the unforgiving way she's restrained. Then I hit the same spot again, and I'm rewarded with a grunt, but no flinch.

"Good girl," I say, then hit the same spot again. No response this time, so I move onto her other cheek. She squirms, humping the bar again, and I know she's well on the way to being completely in the moment. I redden her right cheek with a few more swats of the crop, then work my way down the front of her thigh. There's tension there as she's up on her toes, but even when she masturbates alone her legs need to be tense for her to cum.

I work my way up and down each leg, circling her slowly as she loses track of everything except the pain. I could ask her to do anything now, and she'd obey without question. I enjoy the power, and caress her skin with the tip of the crop, before cupping one breast with my warm hands. She starts at the variation in sensation, then I slap the same tit, hard, and she breathes out a spray of drool in response. She's ready now.

I reach down and switch on the wand, two clicks down from the highest setting. Much higher than normal, but since I'm sending the vibration through the scaffold pole I want her to feel it. She does feel it; her hips move to hump yet again and her hands clench and unclench in her cuffs.

I move close to her ear and speak just above a whisper,

"Ten."

"You're my helpless little fucktoy, and you're going to do exactly as I say."

She moans and nods and humps the bar.

"Nine."

"This body is mine to control," as I bring the crop hard against her mound and she lets out a little squeak.

"Eight."

"I know you've fantasised about this ever since the scaffolding went up. You're a greedy painslut."

"Seven."

"I bet the builders would enjoy you left here for them when they get here on Monday morning. They'd make full use of your holes."

She humps faster at this, so I work with the theme.

"Six."

"Maybe they forgot something, and they're waiting and watching so they can take their turn now. I know you'd make sure they had a good time."

More nodding, her hands fidgeting more.

"Five."

"Perform for us all then, whore. Show them what they're going to get when I let you down."

"Four."

"Don't fucking stop humping. This is your chance to impress your audience with your stamina. Show us all what a good fucktoy you are"

She humps harder still, her lips glistening with the dripped saliva and her own juices. I scoop some up with my finger.

"Three."

I shove my finger into her mouth, and her tongue swirls around it instantly, "Taste how fucking needy you are. Your empty cunthole is leaking everywhere."

"Two."

"Put on a good show, and you might get your holes fucked. You'd like that, wouldn't you slut?"

She nods, eagerly, more spit bubbling and dripping down her chest. She's oblivious to it, focused only on my words.

"One."

"Now make it big, impress me. Show me what a filthy slut you are, fucking the scaffolding. CUM for me. Cum now."

She takes a deep breath, holds it for a second and then groans as her squirt erupts from her and sprays around the cold metal bar. Her toes flex and tense over and over and her whole body squirms hard.

Slowly the pulsing convulsions fade away, and I slide my warm hands over her body. She's warm and sweating, but the cool night air will soon chill her.

I wait for the convulsions to fade, then uncuff her hands, and she leans hard on me. I remove the ring gag, and she smiles an exhausted grin. Then I slip the blindfold up over her head, and her sparkling eyes meet mine.

I half carry her back to the house, laying her down on the sofa before collecting our things from next door's garden. By the time I return, she's almost asleep, and I pull her onto my chest before covering her with a blanket. I listen to her breathing and soon fall asleep with her.