My alarm sounded at 5am, which was standard on a workday. I flapped at it and managed to shut if off after three clumsy swipes. Alarm silenced, I twisted my head round to find the other side of the bed vacant. This was strange because my wife, Tessa, was not usually an early riser. Oh well, hopefully she was downstairs preparing me some breakfast.

We had a pretty conventional marriage, up until that fateful day, and respectively assumed the historically assigned roles of man and woman. At least, that was what I thought. I, Dennis, was the predominant breadwinner, working full-time as an English Literature teacher at a comprehensive school. Meanwhile, Tessa worked sporadically as a teaching assistant. I say 'sporadically' because at the time of which I'm currently writing she worked just two afternoons per week at a nursery group. As such, she had more free time than I, so it became natural for her to cook our meals and complete all other household chores like cleaning and tidying.

She rarely grumbled about this division of labour. Of course, there were the odd remarks about my laziness around the house, but that amounted to mere spousal banter. And, in my defence, I was usually preoccupied with marking students' work or planning future lessons. So it was only right for her to apportion her marital contribution to the housework. After all, I was bringing in the most money to the household.

Still a bit bleary-eyed, I whipped back the duvet and sat on the edge of the bed stretching and yawning. I had this heavy feeling on my chest, which was unusual as I kept myself in pretty good shape. I just thought that I was maybe coming down with some sort of cold.

I began my day as normal, by heading straight to the bathroom for a shower. I grabbed a towel from the radiator in the bedroom and set about my routine. Still not fully with it after waking up, I brushed my teeth and was just spitting out the residual toothpaste when a stray blonde hair strobed into my vision. 'What the hell', I thought, because I had short brown hair, but after initial confusion I decided that it must be one of Tessa's stray hairs that were always appearing in the bathroom. The only logical explanation was that it had somehow made its way onto my head. I gently grasped at it to pull it off, but it didn't budge...it was attached to my head!

My hand rose up automatically. When it reached my hair all it felt was a silky soft mane. Utterly bemused, I convinced myself that it was some sort of wig Tessa had put on my head during the night as a practical joke. I pulled at the hair with both hands, but nothing moved. I did still think that it must be a wig, as it was the only explanation I could imagine for the long blonde hairs on my head, but I was now thinking that Tessa had taken her prank too far and glued it to my cranium.

"TESSA!" I screamed. "What have you done to my hair!?!" My voice was a much higher pitch than usual, but I attributed that to panic/irritation.

I could hear her starting to come up the stairs. Soon she was standing in the bathroom doorway. She was wearing a white tank top and black leggings. Her long brown hair was done up in a ponytail. She also had her running shoes on and was carrying a water bottle. Clearly she was planning on heading out for an early morning run.

"You alright babe?" she asked.

"My hair", I said, tugging at it, "what have you done to it?"

"What are you on about?" She looked genuinely puzzled, which unnerved me.

"This!" I bellowed, pointing to my hair. "I went to bed with brown hair and suddenly I wake up with long blonde hair. You've glued a wig to me, haven't you?!"

"I honestly have no idea what you're going on about. You've always had blonde hair, babe." She was smiling, but a trace of confusion glazed her eyes.

"Fuck off, I've never had blonde hair Tessa! You need to tell me what you've done and help me get it off."

"Um, excuse me! Firstly, don't tell me to fuck off. That's not the girl I fell in love with..."

I was about to interrupt her - 'what is she on about, "girl"?' - but she raised her hand to cut me off and the fire in her eyes told me I'd better not dare say another word until she had finished.

"Secondly, you love your blonde hair; you say it's your best feature...well, second best, after..." Here, she waved her hand in a gesture directed at my chest.

I looked down, and realised I had breasts! And they were huge! I recoiled in horror.

"Babe, I'm starting to worry: why are you acting so strangely?" She approached me and wrapped her arms around my neck. I was facing her, and as her lips approached mine for a kiss, I realised we were the same height.

This can't be happening! What even is happening?!

I had gone to bed, I thought, as a 6-foot-2 man with short brown hair and a decent set of pecs; now, I was standing face-to-face with my 5-foot-7 wife with long blonde hair and a pair of sizeable breasts.

"You OK now?" she asked, releasing herself from me. I wasn't. I still felt like I was dreaming. But I nodded regardless. The nodding was not a conscious movement on my part, though...it was almost as if my body and mind were two separate entities at that moment.

"Good. Now, get yourself showered and dressed for work. Big day, first day back after the summer holidays. Deliver your lessons and have a good day. I'll see you again this evening, when we can celebrate this special day properly. I love you, Denise." Her eyes were strangely hypnotic as she said all of this.

She leant in for another kiss, more of a snog this time, and grabbed my ass as our tongues danced. She then left. I could hear the front door close behind her as she exited the house. I stood for some time in a bit of a stupor.

In some part of my mind, I was still certain that I was a male named Dennis. But the certainty I had felt just a few short minutes ago had faded. The reality that faced back at me as I looked into the full-length bathroom mirror was that I was a female, apparently named Denise. This must be the truth, as the evidence was clearly staring back at me from the mirror. Plus my wife had told me it was so. But the doubt...it never fully dissipated.

Without further contemplation, I got showered, just like Tessa had suggested (ordered?) I do. I then re-entered the bedroom and headed straight over to my wardrobe. As I pulled open my underwear drawer I was presented with a rainbow of different coloured panties on the right-hand side and a series of bras on the left-hand side. Just like I had showered without considered thought, I instinctively grabbed a lacy white bra and matching panties. I saw on the label of the bra that it was sized 36D. This was another reinforcement that it must be mine because Tessa's bra size was 34B.

Why on earth was a part of me convinced that I was a man named Dennis, when all evidence suggested I was, and always had been, a woman named Denise? Was I having some sort of breakdown? Suffering from delusion?

I put the bra on as though I wore one every day (and, increasingly, I was believing that maybe I did; that I was 100% woman and my believing that I was previously a man was absolutely just a delusion!) The bra felt very natural and comfortable around my chest. I then pulled up the panties, which was the first time that I noticed that I had a vagina (but, then again, why wouldn't I? I was female in all other respects, after all!)

I opened the wardrobe doors and my eyes were met with a series of dresses, skirts and tops, all hung up. At the bottom of the wardrobe were some folded clothes (trousers, jeans and leggings). I instinctively reached in and pulled out a light blue floral dress that fell to mid-way up my calves. It was a perfect fit. It was pretty, but not sexy - perfect for teaching in a secondary school!

All dressed, I moved over to another drawer, pulled out some makeup and effortlessly did my face up. My hair fell naturally down to my shoulders. I looked at myself in the mirror and the reflected image showed an attractive 28-year-old woman. Not too tall or too short, and not too fat or too thin. With a pretty smile, gorgeous blonde hair and ample bosoms, I was the archetypal attractive teacher who the schoolboys (plus some of the girls) would inevitably develop a passing crush on.

But deep in the back of my mind I couldn't help thinking that this wasn't truly who I was. There was a nagging voice trying to tell me something, but its sound was muffled by a thick blanket obstructing its passage to the forefront of my conscious. All I could actually hear was: "You deliver your lessons and have a good day..." before these words trailed off into an echo.

But that was enough to spur me into action: these were my instructions for the day, and I had to fulfil them. That's what my conscious mind was telling me.

I looked at the bedside clock, saw that it was already 7am (how had the time passed so quickly?!) and headed straight downstairs. I put on a pair of white pumps that sat by the front door and walked out to my car, before driving to school to begin the Autumn term.

The day passed by without any noticeable incidents. When I arrived at the school, I walked straight to my classroom and prepared for the day ahead. I then taught my first lesson, year 7, at 9am; year 10 followed at 10am; year 12 came in at 10.30am; year 8 then at 11.30am; and I finished up with year 11 at 1.30pm.

In every single class, the pupils referred to me as Mrs McGrath. I also instinctively wrote that same name on the whiteboard at the beginning of the day, before I'd even interacted with any of the pupils. McGrath was Tessa's maiden name; I had a pestering thought that she had become Tessa Mellon when she married me, who I thought was Dennis Mellon, but apparently not. She was Tessa McGrath and I was her wife, Denise McGrath. That was the reality in which I now lived.

I stayed behind for about two hours after the children departed for the day, as standard, and then headed home. It was 5pm when I walked through my front door. I walked into the living room and saw Tessa sat on the sofa watching 'The Chase'. She was wearing jogging bottoms and a hoodie and was snacking on Doritos and a dip.

"Good day, Denise?" she asked.

"Yeah, not too bad", I replied. I was still so confused about everything that was happening. But if my wife was telling me that I was a woman and always had been, that would have to do. Where these doubts and my imagining of a past life were coming from, I do not know, but I was hoping they would pass by soon.

"We better be getting ready in a bit", she said. "Restaurant is booked for 7pm."

"We going out?" I asked.

"Obviously, not every day you get to celebrate your five year wedding anniversary."

We watched the rest of 'The Chase' together, eating the Doritos. As the end credits were rolling, she got up and took me by the hand upstairs to the bathroom. She ordered me to shower and then to go to our bedroom to get changed. She told me to wear something "colourful and sexy". She had already showered and would get dressed in the spare bedroom. I did as I was told.

Her words were "colourful and sexy" so I considered my options before selecting a yellow lace bra and matching thong. The label on the thong said that they were from Ann Summers. Lingerie on, I also pulled a pair of tights from the draw below my bras and panties and put them on too. I decided on a bubblegum pink sleeveless mini dress that just about covered up my bra straps. I did my makeup, let my hair fall naturally to my shoulders, and walked out to the landing.

Tessa walked out at the same time. Likewise, she had chosen to wear tights. Her dress was an off-the-shoulder black bodycon mini dress. She looked divine, with her hair worn curled over one shoulder. We headed downstairs, both put on a pair of high heels (her's were black while mine were pink) and walked hand in hand to the restaurant.

We ate at Luciano's, a nice little Italian restaurant about a fifteen minute walk from our house. It was where we'd had our first date, which is probably why Tessa chose it again for our fifth wedding anniversary. We were served by a lovely young man called Giovanni.

What was noticeable was that all of our conversation over food was directed by Tessa. She was the one who reminisced on our lives together, while I just listened to her and occasionally pined in, but not with anything substantial. Everything she said rang a bell and none of it appeared to be fabricated. But it felt as though there were important bits missing; deliberately omitted, almost. Yet, I couldn't quite tell what those missing bits were, nor why they were important. So, instead of straining to remember or figure out what I couldn't quite put my finger on, I simply went along with Tessa's word and enjoyed listening to the mellifluous tone of her voice. I was captivated by every word she said, and was unable to argue or contradict anything that came out of her mouth. Not that I wanted to; after all, I'd had a weird day. I now just wanted to enjoy some special time with my wife.

After we'd finished our meals, Tessa handled the settling of the bill. This, again, struck me as odd: wasn't I always the one to pay the bill? No point contesting, though, as I imagined that the debit card she used to pay was the one for our join account, anyway. Plus, she had insisted on sorting it. I did not contest this with her.

We left the restaurant and headed for home. We got in just after 9pm and headed straight upstairs. Tessa was eager to cap off our evening together with some 'us time'.

"Go into the bedroom and strip to your underwear. Lie back on the bed and close your eyes. I'll be in shortly." She said this decisively. And who was I to argue with her?

I did as she instructed. I walked into the bedroom, removed my dress and tights, and lay back on the bed, eyes closed, in just my yellow lingerie. Not long after, I felt her presence enter the room. She jumped onto the bed then crawled on top of me. I could tell from the feel of her that she was already naked. This immediately turned me on.

Eyes still shut tight, she started snogging me and then slipped her hand down my panties. She inserted two of her fingers into my vagina and began fingering me. It was a sensation I was sure I'd never felt before, despite supposedly being in this lesbian marriage for 5 years. But, oh was it joyful! I let out a quivering moan as she expertly manoeuvred her digits in the heart of my cunt. It wasn't long before I came.

She removed her fingers, which were now covered in my juice.

"Open your eyes", she said. I did.

"Lick my fingers", she said. I did. They tasted delicious.

"My turn now", she said, lying on her back, legs spread out. "Use your tongue."

I crawled towards her, tongue hanging out. I was like a dog, eager to please. She held back the forward strands of my hair as my tongue explored her cunt. I felt inexperienced at this, but I continued to do as she asked. I was going for about ten minutes when she told me to stop. I removed my face from her crotch immediately.

She reached down into the bedside drawer and pulled out a double-ended dildo. She slathered it in lube before pulling my panties down and off. She then inserted one end of the dildo into me. I gasped as it first entered me.

She positioned the other end into herself, and we both edged further along the shaft. We were millimetres from one another now. She reached around and pulled off my bra. We were both now fully naked and staring into each other's eyes while aggressively thrusting on the phallus. I was moaning loudly and continuously; she moaned too, but less vociferously. Again, I came after very little time. She remained thrusting a little while after I had finished.

I was sweating profusely while Tessa looked like she'd barely broken a sweat. We removed ourselves from the dildo, which Tessa flung to the floor, and lay back on the bed facing each other. I was exhausted, but very satisfied. It felt to me like I had just had the best sex of my life...but I've no idea why or how, because for some reason I had no conceivable memories to compare it to. I have no idea how it was for Tessa because she was obviously trying to divert conversation away from what we'd just done.

We spoke briefly about the week ahead. It was a mundane conversation to follow what had occurred moments before, but it was the conversation she directed and I simply responded in kind to it.

It was late by now. As it was a school day the following day, I needed to hit the hay. We spooned for a bit, with me as the little spoon (this felt unusual, but not unpleasant), and then I drifted off to sleep. It had been a strange day, but I had now forgotten all about my paranoia from this morning. Lying in bed with my gorgeous wife, I was now satisfied in my mind that I was Denise McGrath, wife of Tessa McGrath. Always had bed, always would be. We were a happy, young, infatuated lesbian couple. Life couldn't be any better!

That was what I thought, at least. But the events that thereafter unfolded would put my thoughts from that morning into much clearer context...