The moon threatens to come out from behind the clouds again and I have to jump down to the paving stones of the patio beneath. There is a small wall beside the greenhouse which rises to within a metre of the top of the estate wall; that's my escape route. There are infrared-sensing security lights on the wall of the house and if they go on then the whole thing's off; I'm up and over the wall and back into the woods and away.

I walk quietly over the patio, onto the grass and towards the house, just waiting for the blaze of light from the security lamps. It doesn't happen. I reach the lower patio where the garden furniture stands by the side of the tarpaulin-covered pool and crouch down by the ghostly perforated shape of the cast-iron bench. I feel up inside the overhang where the back of the bench joins the arm, the leather of my gloves catching on rough splinters of metal. I can't feel enough. I take my glove off and try again, the metal cold and edges sharp against my skin. I feel the putty, then the embedded key and its short length of string. I take hold of the string and pull gently. The key comes out, clinking quietly once. I put my glove back on.

I walk carefully past the conservatory to the back door of the house, slide the key into the lock and turn it. The door opens silently. The house is warm inside and smells of washing powder. I lock the door; as I move away from it, a small, faint red light comes on with a tiny clinking noise, high up in one far corner of the room. The sensor doesn't set the alarm off; the system isn't armed.

I move very slowly through the utility room and into the kitchen (another little red light clicks on). My boots squelch and squeak on the tiles. I hesitate, then kneel and quickly take the boots off, leaving them by the dishwasher. When I stand up I see the wooden block full of knives on the work surface, just visible by moonlight next to the gently gleaming stainless steel of the sinks. I pull out the largest of the knives, then turn and leave the kitchen, heading down the corridor past the dining room and the study to the stairs. Beyond and to the side is the split-level lounge; a shaft of orange street light sifting through the trees round the front garden shows leather settees, chairs, bookcases full of videos, CDs and books, a couple of coffee tables and a big metal hood over a raised central fireplace. Another sensor high in one corner glows red as I move towards the foot of the stairs.

The carpet on the stairs is thick and deep and I make no noise as I climb to the top, then pad along towards the master bedroom, tripping one more sensor. The bedroom door opens with only the softest of creaks.

At the head of the wide double bed there is a weak green glow. As I move round I see the numerals of a digital clock. The lime-coloured light spills faintly out onto white sheets and a single, sleeping face. I go closer, very slowly, the knife held in front of me. I watch her breathe. One of her arms lies outside the covers, hanging out pale and naked over the edge of the bed. She has short, dark hair and a slim, slightly boyish face; thin, dark brows, thin nose, pale lips with the hint of a pout, and a sharp triangular chin matching sharp, high cheekbones.

I creep closer. She stirs. I reach forward, the knife in one hand, the other glove touching then gathering and balling a fistful of duvet and then pulling it sharply, throwing it away behind me as I leap forward, seeing her pale nakedness in the same instant as I slap my hand over her mouth; her eyes open wide and she starts trying to push up; I force her back down into the bed, hand still over her mouth. I raise the knife so she can see it. She struggles, eyes widening further, but I pin her to the sheets with my weight and keep the glove firmly over her mouth even though she isn't making any noise. I rest the blade of the knife against her throat and she goes still.

"Make a noise and you're dead, understand?" I say. She seems not to hear, staring up at me. "Understand?" I say again, and this time she nods quickly. "Warning you," I tell her as I slowly take my hand away from her mouth. She doesn't call out.

I push myself up, still keeping the knife near her throat. I undo the zip on my jeans. I'm not wearing any underpants and my cock falls out, already hard. She's staring into my eyes. I see her swallow. A pulse beats at the top of her long, white neck, under her chin. Her hand is creeping to the side of the bed. I look at it, and it stops. Her eyes look terrified now. I put the blade of the knife against her neck again and look down to the edge of the mattress. She's trembling. I feel under the edge of the mattress, above the wooden frame of the huge bed. I feel a wooden handle; I pull out a ten-inch hunting knife with a serrated blade. I whistle softly, then throw it across the carpets towards the windows. She's staring at me.

"On your front," I tell her. "On your knees, like a dog. Now."

She starts to breathe raggedly, mouth open. Her whole body is trembling.

"Do it!" I hiss.

She rolls over, onto her front, then gets up onto her knees, taking the weight of her upper body on her hands.

"Face on the sheets," I tell her. "Hands up here."

She rests her face on the sheet and puts her hands behind her. I take the handcuffs from my pocket and snap them over her wrists. I stop to put a condom on, then climb onto the bed behind her, put the knife onto the sheets just within reach, grip her hips with both hands and pull her onto my cock.

She shouts as I enter her. She's soaking wet and within a few thrusts I'm ready to come and she's panting, then grunting then calling out, "Oh, fuck, yes!" and then it's all over and I collapse over her and then fall off her and almost cut my ear on the cool blade of the kitchen knife lying on the sheet.

She lies there on her side, facing me, watching me, still panting, hands still trapped behind her back, a strange, charged expression on her face, and after a bit she says, "Is that it?"

I breathe deeply and say, "No."

I haul her roughly back up onto her knees with her face down on the sheets again and spread her buttocks and stick an index finger into her anus, sliding it quickly half into her. She gasps. I position my head above her backside and let some spit fall down onto where the knuckle is caught on the ring of muscle, then push my finger fully into her. She gasps again; I start to move the finger in and out, stroking her clitoris with my other hand. I use two fingers after a while, then I'm hard again; I pull the first condom off and put on another one, then I spit onto my rubber-sheathed prick and, guiding it with my fingers, ease it slowly into her rectum.

She comes screaming; I don't think I'm going to but then I do.

We collapse together onto the bed, breathing in time. I pull myself out of her. There is a faint smell of shit. I undo the handcuffs and lie there, holding her. She pulls the ski-mask from my head.

"Where are your shoes?" she whispers after a while.

"In the kitchen," I tell her. They were muddy. Didn't want to make a mess."

She laughs quietly in the darkness.

"But I was in control," she says, over the noise of the streaming water as she soaps my shoulders and back. "All I had to say was your name, and it was all over. That's what we agreed; I trust you."

"But what's the difference?" I ask her, trying to see her over my shoulder. "Anybody watching that would have said I was a rapist and you were being raped."

"But we knew different."

"But is that all it is? I mean just thinking that? What if it had been a real rapist?"

"What if it had been the wrong house?"

"I checked the furniture."

"And you were just you; you moved like you, spoke like you; smelled like you."

"But-"

"Look; I enjoyed it," she says, soaping the small of my back and my buttocks. "I don't think I want to do it again, but it was interesting to live it out. But what about you? How did you feel about it?"