Sunday went by at a crawl. I’d already prepared everything before lunch, so the last few hours before I expected Fiona to arrive felt agonisingly slow. Should I have set an earlier curfew? Should I call or message her to make sure she hadn’t forgotten? Absolutely not - this was just a casual arrangement that was convenient for both of us. Seeming too invested would definitely raise some red flags, and even if the conditioning I’d put in place on her held, her friends would definitely get suspicious. I checked the routines and fail safes I had programmed into the equipment again, even though I’d already checked over them ten times already. I went over the living room for dust, despite it already being spotless. I thought maybe I could distract myself by cooking or playing a game or watching a show, but it all seemed so pointless when soon I’d have my test subject alone and completely isolated for me to test my improvements with. She wouldn’t be scared. She wouldn’t even know anything was out of the ordinary, or at least not to the extent that she would think something was amiss. The beauty of the technology was that the receiver really didn’t think that the thoughts, ideas and emotions being artificially impressed upon their mind were anything other than their own, so as long as I didn’t do anything too outlandish, Fiona wouldn’t have a clue. And I’d make it enjoyable for her, too. Not only by doing things that she would conceivably enjoy, but also by allowing my own enjoyment to bleed into her. With careful sculpting, I should be able to shape her desires so that she comes to look forward to every night with as much anticipation as I did. And I’d come clean with her eventually. It was the only moral thing to do. Eventually. After such a time as she would be receptive to the idea, perhaps. To avoid any misunderstandings. I felt my skin go cold with anxiety when the doorbell rang at four-fifty, and I needed to take a second to put on an air of disinterested reproach before opening the front door. “I was worried you’d already forgotten,” I said, taking in the casual outfit and knee-high travel case. “Sorry!” Fiona said with an apologetic smile. “I just forgot a few things at the last minute. Are we still good?” I stepped back into the house as my answer, leaving the door open for her to follow. “I need to get started immediately. Feel free to put your stuff away - I just need to have you somewhere in the house, awake, sober and alert. Other than that, you’re welcome to do whatever. I’ve got a few streaming services already signed in on the TV, just don’t go watching pay-per-view or anything inappropriate. You’ve got food and drink?” Fiona gave her case a gentle kick. “Yep. I’m all stocked up.” “Hm. Well, there are some frozen meals in the fridge, coffee and tea if you ever run low. I’m heading downstairs now. Any questions?” Fiona shook her head. “Alright, I’ll be back up in a few hours.” My steady descent into the basement belied the furious beating of my heart as I brought the equipment out of sleep mode and set the timers for the evening. The short-term dives had been successful enough, so I felt confident that giving myself a full hour behind her eyes shouldn’t pose any significant danger. With the clocks ticking, I lay down on the bed and waited for my perspective to shift. Unlike before, there was no sense of disorientation; going from supine and relaxed to standing tensed with a heavy weight in my hands. In fact, I found Fiona in a very similar position to my own body: Laid out on the couch and browsing through movies with one hand while holding her phone in the other. I decided to take my time, as there was no hurry and I didn’t want to risk causing her or her friends any alarm through unusual behaviour. It was just as well, as she spent the first thirty minutes texting her friends for recommendations while also allaying their fears that anything strange would happen that night. Eventually I grew irritated at the persistent line of communication, and like pressing my face into a pillow, I pushed that impatience into Fiona’s own mind. Suddenly bored of messaging her friends, she said her goodbyes before searching for something to watch in earnest. A whisper into her subconscious drew her to a horror film with erotic themes, and I observed that she responded with a small degree of excitement at the opening scene, even without my influence. I felt her heartbeat quicken and the electric stirrings of arousal run across her skin. She breathed in deeply, chewing gently on her thumb as the lovers onscreen giggled in their illicit tryst. Maybe she wouldn’t need as much manipulation as I’d first expected. Through my own interest, I began to coax Fiona’s own mind away from what was happening on the TV and moved it instead to the response it was having on her body. I saw our gaze flit down to the faint outline of our nipples barely visible through the fabric of the top we wore. At my silent suggestion, a hand rose slowly to one breast and began to stoke the tiny bump, causing a lightning tingle to fill our chest. She continued without my instruction, and I was able to float on the alien bliss of teasing myself in a woman’s body. I wondered about the rest of her, and our shared vision focused beyond our breasts to the flat stomach and long legs stretched out along the couch. A gentle push made Fiona raise her hips up and flexed her lower body luxuriantly, and I was amazed at how good even the simple act of stretching felt in this younger flesh. Still taking care not to overstep myself, I pushed a little more of myself into her mind, feeling her willpower yield around me as though I were sinking my fingers into mud. I wanted to see her. All of her. Not from my perspective as a stranger whose house she was staying in, but through her own eyes. Ignoring the screams coming from the television, I felt our body lurch upright as she swung herself into a standing position. One of the living room walls was a floor to ceiling mirror whose edges were lined with white lights angled towards the centre. I’d had it installed during the months of preparation work for this exact moment. A little bit of clever interior design to make the room feel more spacious, but also a convenient spot for anyone keen to admire themselves. We looked at our body appraisingly, and I deferred to her experience when choosing what angles to check herself out from and for how long. She posed our body this way and that, dancing a little just to see how it looked from one angle or another. I’d hoped to secure a test subject that was physically attractive, but watching the body I had stowed away in gyrate seductively made me appreciate my incredible stroke of luck. It was quite impossible to completely contain my own desire, and the expression on our face steadily became less critical and more entranced by our own beauty. I pushed Fiona forward gently, and felt our legs slowly, gracefully take us closer and closer to the glass. The light coming from all sides illuminated our shared face beautifully, and we approached our reflection as though enthralled by a lover. Raising a hand out to herself, the sudden physical with cold glass seemed to snap Fiona out of her reverie. Both the sensation and Fiona’s sudden sobriety came as a shock to myself, shaking me out of the beguiling illusion that we were one person. I was just steadying myself to retake the reins when I felt my senses being dragged out of Fiona’s body and dumped back into my own. It was the worst timing imaginable, and I imagined Fiona panicking upstairs at her own strange behaviour. I’d resolved to influence her behaviour subtly and observe the results clinically, but I’d lost myself in the shared excitement we had felt as a single entity and let it get completely out of control. Wasting no time adjusting parameters, I hit the execute button again. I had expected to find Fiona on her phone calling for help, or worse still, outside the house and leaving the limited broadcast range of my equipment. Instead I was surprised and more than a little flabbergasted to see my - HER - reflection still intimately close to the glass but this time with no shirt or bra to be seen. A soft gasp escaped our lips as my hurried intrusion caused her to involuntarily shiver. Realising that there was no danger of flight or discovery, I watched in passive awe as Fiona began to slowly sway back and forth, her fingers tracing circles around the outline of our breasts. I felt the electric sensation crawl through our chest, down our spine and between our legs, causing unfamiliar muscles to flex and twitch. Not wanting to risk pushing Fiona to any behaviour that she might reflect poorly on, I relegated myself to the role of observer from within her body. That’s what I told myself, at any rate. In practice, I realised that I was unable to contain the voyeuristic thrill of watching the woman whose body and senses I now shared tease herself in the mirror, and I realised that she too must be experiencing a sense of detachment from herself that made the experience more than the usual act of self-pleasure. Ultimately, we were both enraptured by the experience of watching through a stranger’s eyes as she pleasured herself in the mirror. Having lost track of time, I couldn’t say how long it was before one hand dropped to trace itself down her stomach, coming to rest at her waistband. Even through the fabric, I could feel our fingers gently stroking out inner thighs. Fiona moved as if to return to the couch, and I was unable to stop my sudden flush of disappointment when her vision turned away from the mirror. Cursing myself for allowing my emotions to once again inadvertently bleed into here, I felt our body hesitate before looking back into the mirror. Fiona stepped back into view, looking herself up and down before straddling the centre line. I held myself as aloof as possible from her emotional state, feeling our gaze crawl up and down our body, and it was to my genuine surprise when she suddenly tucked her thumbs into her pants and bent at the waist, pulling pants and panties down in one smooth motion. I felt a shiver pass through us - partially from the sudden cold on our bare skin, partially from my own shock at Fiona’s bold action. Fiona stood up and stepped out from the puddle of her discarded clothes to bathe naked in the fluorescent light, hands on her hips and shifting her weight subtly from one leg to the other. It was a glorious sight to behold, and I found that I had completely lost track of where my emotions ended as hers began: We both exulted in our nakedness, devouring the sight of our body as we flexed and posed. I could not say whether Fiona had been a narcissist before I had slipped into her mind, but she revelled in her beauty now, running her hands up and down every inch of her skin, our combined lust never allowing her gaze to wander from the glass. Her body jumped when she brushed a finger against her pussy, as though she were surprised to find it there. In a way, she was: It was a sensation completely alien to me and my own shock had made the experience somehow new to her in turn. It didn’t matter that she’d lived with it her entire life or how many times she had touched herself before now: For some strange reason, doing it now felt like the first time. I was overcome by my own anticipation and wonder; unable or unwilling to stop her as she ran a finger back and forth between her legs, our body opening ever so slightly as we gazed into our own eyes. I would never call myself a prude, but I also have never felt the need to experiment. It wasn’t an aversion to anything beyond the vanilla experience as such, but my experiences both with partners and by myself I can say with confidence were decidedly average. So the sudden prospect of being penetrated - not so much against my will but certainly without my volition - in a stranger’s body with a stranger’s anatomy left me in such a state of paralytic apprehension that I was unable to stop her. Unable to do anything as I felt our finger slowly push its way into our unresisting body. Our body quivered, and I realised that just as I was experiencing her arousal, she must be aware at some subconscious level of my own unease at the unfamiliar sensation. In a strange way, she was assaulting herself: Both the aggressor and the victim, both dominant and afraid. Our finger came to a halt as it buried itself inside us up to the knuckle, reaching as deep into us as it could reach. We let out a faint moan as Fiona curled the digit within us, tracing the contours of our insides as she drew it slowly back out. I felt a stinging tightness in our chest, and I realised it was because Fiona had taken one breast in the palm of her hand and squeezed it against her body - an otherwise painful experience made exquisite by our own elevated lust. She wanted to go further. I wanted to go further, and as I began to cast my mind around the room for something we could reasonably use as an aid, my vision of the room bled away as I was once more sucked back into my own form. Being pulled away from Fiona’s warmth and energy and arousal into a body made sluggish from laying inert for two hours felt like being robbed, and a genuine anger rose in me as I sat up and swivelled towards the terminal. She was clearly no stranger to indulging herself, and the very nature of the technology was such that anything I made her do would seem to her as if she had thought of it herself. I had one more hour before she would reasonably suspect something was amiss, and I did not intend to let her waste it through half measures. Restarting the timer, I lay down and this time felt a noticeable jolt as my mind was rerouted into her body. More than just a jolt: I had set Fiona’s nanites to full receive mode and myself to full broadcast. Her body shivered violently as the link to its owner’s mind was suddenly cut off and instead taken over by my own. Muscles spasmed and twitched, a breath that had started as hers choked in her throat as it became mine and our eyes rolled up as her body surrendered itself to the forceful takeover. I feared I may have overdone it by asserting such direct control, but as I regained my composure, I realised she had laid herself out on the bed I had made for her. A hard sensation lodged inside my turned out to be a small sex toy, no larger than a pencil and buzzing impotently. I tossed it aside with a relieved grin. No doubt Fiona thought herself still in control, and had probably rationalised my invasion as an unusually overpowering climax. My heart was racing, my skin was radiating heat and my hair was damp. I stood up from the bed, revelling in the control I now had over the elfin body I had commandeered. I stretched, I twisted, examined myself up and down and the fires of arousal only grew hotter. My body - the body I was controlling - wanted more than the paltry pleasure Fiona’s toy had been able to give it. I considered my options, discarding each one in turn. If Fiona had brought something more substantial, she would have used it. There were any number of household items around the living room and kitchen, but the few that were of a size were unreasonable even in my sex-hungry state and would definitely seem incongruous to Fiona’s memory once I returned control of her body. As I ran down the list of possibilities, I realised that I was only herding myself towards the one obvious answer. It was dangerous, but given Fiona’s current mental state, it wasn’t impossible. In fact it was the only option I wanted. My stolen body craved it. Maintaining the illusion that Fiona’s body was still her own, I hurriedly put her discarded clothes back on, ignoring burning heat from my skin and the cold, damn sensation on my crotch. I tip-toed over to the basement door and hesitantly knocked, before pushing the door open when no answer was forthcoming. In the cool air beyond, I crept silently down the concrete steps, pausing every now and then as though to listen, as though I didn’t know my body was fully incapacitated only metres away. Once in the hallway below, I turned and peered through the first door to find my own body, prone in its chair with its eyes closed and its chest slowly rising and falling as though in a deep sleep. “Mister Riley?” I croaked out, my throat dry with apprehension. I licked my lips, tasting the barest hint of salt from my own sweat. Creeping forwards, I whispered again. “Mister Riley?” It felt comical, behaving in this way, but the act of puppeteering Fiona’s body; forcing it to follow the ridiculous script I had written for her while she watched from within herself - oblivious to the fact that it wasn’t her doing it - was too delicious to describe. Eventually I worked up the “courage” to sidle up to my original body, my gaze flitting between my “sleeping” face and the fly of my pants. With exaggerated care, I watched my delicate fingers draw the belt from its buckle, pop open the button at my waste and draw the zip down, revealing my boxers underneath. My heart raced and my mouth went dry as I undid the buttons, pulling the fabric apart to reveal my own limp penis. I was actually shocked at its size, being much larger from Fiona’s perspective. As though removing a chick from its nest, I reached out and cradled it in my hands, feeling the warmth of my own body against Fiona’s palms. How much of what I was about to do really my own idea? I would never have dreamed of this happening two hours ago, and even now it seemed surreal. Looking up at myself, as though expecting my body to suddenly start awake, I brought the tip of my own penis to my stolen lips, part them open and gave the head a hesitant lick. It didn’t really taste of anything - to both my relief and vague disappointment - but the sudden twitch in my hands as it responded to me made me light-headed with excitement. I licked it again, feeling the beating of my body’s heart unconsciously channel blood to the cock in my borrowed hands. I pressed my lips against the tip, holding them there for almost an entire minute as my cock grew larger and larger. Before long, Fiona’s face had been pushed away from my crotch, her hands no longer able to encircle my girth as it came to full erection. Barely able to breath, I allowed her jaw to relax and pushed her head forward, letting my cock pry our lips apart and slide into our mouth. I cannot begin to explain what compelled me - the instincts of the body I inhabited perhaps, or my desire to debase it - but I quickly found myself bobbing Fiona’s head up and down the length of my cock, feeling the rubbery texture of the head against my tongue and it slid back and forth. The faint funk of precum made me recoil suddenly, and I wiped my tongue hurriedly on my sleeve. While it didn’t diminish my arousal, it was a reminder that I hadn’t brought Fiona here simply to pleasure my unconscious body. With an awkward desperation, I stripped naked, gasping slightly at the cold basement air on our damp skin. I also pulled both pants and underwear down my original body, leaving me naked from waist to knees. I straddled myself, pressing my pussy against my still-hard cock, feeling the warmth of my flesh and the pulse of my heartbeat where the flesh met. Too drunk on arousal to wait, I took the shaft in one hand, raised myself up and moved it into position between my legs. Even the sensation of it sliding against my lips made me tremble, and I couldn’t stop myself crying out quietly as I lowered my body slowly onto it, feeling it push me apart. I shuddered again when Fiona’s crotch made contact with the base of my cock, and I felt my borrowed pussy spasm, tightening around myself. Gingerly, I leaned forward until I was pressed against my own chest, feeling my cock shift inside me as the angle of pressure changed. I avoided looking at my own sleeping face, but instead kept it pressed against my shirt as I began to rock back and forth, feeling my penis slide out of me until only the tip was still inside before pushing myself back onto it again. I quickly built up a rhythm, until the silence of the room was replaced by my laboured breathing and the slap of my thighs against myself. I don’t know if I’d consciously considered the possibility, or if I did, if I would have cared. I just remember feeling my cock begin to twitch inside me, and before I realised what it meant, a thick heat began to squirt itself into me. Carnal instinct took control again, and I thrust my stolen flesh against myself, trapping the warmth deep inside me. My legs clenched themselves around my sleeping body’s waist, and I cried out as an overwhelming euphoria took hold of me. I could feel the last of it pumping out of the head of my cock into the core of my being. I don’t know how long I lay on top of myself. I wanted the moment to last as long as possible, while also dreading the moment my softening cock finally slid out of me and the mess it would leave. It was by pure chance that I spotted the display on the monitor showing I had less than ten minutes before the transmission would end. I pulled myself away, shivering at the slimy sensation between my legs and groaning when I felt it begin to drip down the inside of my thighs. In a comedy of indecision, I debated which of my bodies I should wash first and quickly settled on a compromise: I balled a handful of tissues into my panties and put them on before getting dressed and running to the kitchen for some paper towels and hand soap. There was no point in worrying how Fiona would rationalise knowing where everything was: I just needed everything cleaned before “I” woke up. I washed the mixed fluids from my penis and crotch before awkwardly pulling my pants and underwear back in place. There were some damp patches on my male chest where I had drooled a bit as Fiona, but there wasn’t much I could do about that. With my original body as clean as it could reasonably be, I took everything back upstairs with sixty seconds left on the clock: Just enough time to put everything away and sit back onto the couch, only to remember that a handful of slimy tissues were stuck between my legs as they were pressed into my crotch. The last sensation I experienced that night in Fiona’s body was a shudder of revulsion before I opened my eyes in my own body: Strangely relaxed, although slightly uncomfortable where my briefs had bunched up and my penis was still leaking a bit of leftover semen. I made a point of being as noisy as possible climbing the stairs out of the basement, and when I opened the door into the living room, I found Fiona pressed against one side of the couch, her legs pulled up almost protectively against her. Her nervousness and embarrassment were painfully obvious, but it wouldn’t have done any good to draw attention to it. “Hey,” I said, trying to ignore the memory of being pumped full of cum. Trying to ignore what it was like to wear that face, those breasts and those legs. “Hey,” Fiona squeaked. “Anything happen?” Fiona shook her head with the kind of innocent smile that communicates complete guilt. “Good. What did you get up to?” “Um, nothing!” Fiona said, eyes darting around. “Just… watching a movie!” We both looked at the screen, whose credits had been rolling for so long that the streaming service had started to recommend other shows. “Any good?” I asked. “Yeah! I mean, not really. I wasn’t paying that much attention.” I let the lie hang in the air for a while. “You didn’t fall asleep, did you?” Fiona shook her head emphatically. “No! Absolutely not. Definitely not, I’ve been awake this whole time.” Out of mischief, I grunted and shifted my waistband as though in discomfort and watched Fiona’s face go slightly pale as her gaze moved to my crotch. “Alright, well I’m done for the evening. There’s only so much research I can do in one night.” “Any good?” Fiona asked, and I could see her jaw tense as she regretted drawing the conversation out even longer. “Results aren’t what I expected,” I said, shifting my pants again. “I feel relaxed, but also a bit uncomfortable. I’ll have to keep testing to get more data.” Clearly unable to help herself, Fiona spoke again. “How were you expecting to feel?” “Well, it’s a kind of induced hypnosis,” I lied. “I didn’t know what I was going to feel, just that I was going to be completely unconscious while it was happening.” Fiona hesitated before asking, “Any weird dreams?” I held eye contact with her for a long time, contemplating just telling her the truth. I decided against it. “No. None that I can remember, anyway.” Fiona seemed relieved, and was able to stop herself from saying anything more besides wishing me a good night. I was tempted to return to the basement for some “calibrations,” but I was honestly completely exhausted, despite my body having done very little. I was emotionally drained: I’d gone much, MUCH further with the experiment than I had planned and experienced sex in a way that left me feeling profoundly empty and alone, especially because as far as Fiona was concerned, I shouldn’t have any idea that it had happened. It wasn’t something I had the energy to process at the time, so true to my word, I showered and went straight to bed.