I woke with a start, my heart suddenly pounding as the memory of last night was fresh in my mind. For a few seconds I wasn't sure if any of that stuff really happened, or if it was merely some sort of bizarre dream.

Then I sat up and my heart skipped a beat as I realized it was no dream.

"Oh my gods!" I gasped as I stared down at myself. I gasped again at the sound of my voice. It was undeniably the voice of a girl, soft and high-pitched.

I was still naked, sitting atop my bed. And I was a boy no longer. My arms and legs were smooth and slim, hands and feet were small and delicate. My waist was narrow and my hips wide. Looking at my chest I realized I'd been blessed just like all the other women in our family. My boobs were ample, in fact they looked even bigger than Cathryn's. The soft heavy orbs were tipped with fat pink nipples that tightened and grew hard as I stared at them.

My hair was much longer than before and it had taken on a lighter tone than it used to be, it wasn't quite as light as Cathryn's though. Mine had a red tint to it, I was more of a strawberry blonde than a pure blonde. And finally, between my legs was my new womanhood. Delicate pink folds beneath a smooth soft mound.

There wasn't any hair at all there which surprised me. In fact my arms and legs were quite smooth and hairless as well. I was no little girl though, the curve of my chest and waist and hips confirmed that.

I added that to the list of things I would be talking to my sister about at some point. As happy as I was at the results, I had a lot of questions about the process.

The other bed was empty, no sign of either Cathryn or her dress. The light coming in through the window told me it was morning, so I assumed she was already up and in the other room.

I slipped out of bed then froze a moment. Something about the room was different, it seemed larger than I remembered. I wasn't sure what that meant, but let it go for now as I wondered about clothes. I had none, I hadn't even thought about that before-hand.

On the other hand I didn't feel like I needed anything, I still felt warm like it was a hot summer afternoon. For the sake of decency though I figured I should wear something, so for a temporary measure I took one of the thin blankets from my bed. I draped it over my shoulders and wrapped it around so I was fully covered, then found myself frowning. Even the blanket seemed larger than I remembered.

Finally I emerged from the bedroom, to find my sister sitting at the table munching on some stale bread and sipping weak wine. She was wearing that same dress she had on yesterday, and the polished wood box was still on the table where it was left last night. It remained closed for now.

"Oh my goddess look at you!" Cathryn exclaimed with a wide smile. "Valeria you are absolutely adorable!"

My cheeks coloured as I moved to take the other chair, then I frowned again. The seat and table were both bigger, higher than they were before. As I pulled myself up into the chair I discovered another surprise, my behind was bigger and apparently more padded than I was used to.

I continued to blush as I stated, "I have a lot of questions for you Cathryn."

"I'm sure you do," she grinned. "But first let me ask you something. Are you happy?"

I gulped, "I... Yes, I am. This is amazing and incredible."

"Good," she was still smiling as she gestured to the wood box. "There's two potions left little sister. The process isn't over yet."

"Oh," I frowned. "But this is perfect, what's left to be done?"

My sister replied, "It may be prefect, but it's not yet permanent. We need to complete the process to ensure you don't revert back again."

That sent a shiver of fear through me and my eyes widened. "Ok, let's do it then. I don't want to go back. I never want to go back!"

"Good girl," she said with a smile, and those two words sent another flutter through my heart.

I watched as she reached out and opened up the wood case again, then she picked up the fourth potion and offered it to me.

It contained a thick white liquid, and when I drank it I found it tasted like sweet heavy cream. It reminded me of something you'd pour over fresh berries.

After drinking it down I carefully put the empty vial back in the wood box, then looked to my sister again and asked "What's next? Actually what did I just drink, what will that one do?"

Cathryn was still smiling as she replied, "That one will give you some advantages when it comes to being my apprentice, and a boost when it comes to cultivation."

I frowned, "That sounds like a good thing, but what do you mean by cultivation? Like crops or something? Are we going to be growing our own herbs and things?"

Her smile shifted slightly as she seemed a bit more amused, "Ah right, you don't know about cultivation yet. Don't worry little sister, I'll teach you everything you need to know. We'll be helping each other with that."

Something about the look on her face left me feeling somewhere between nervous and excited.

While we were waiting for that latest potion to do its thing I asked, "So back to my questions Cat. What the hell was that last night? Did we really have sex or did I just imagine that?"

"We had sex," she replied. "I told you it was part of the process, a catalyst to trigger the transformation."

I frowned, "But you're my sister. That's... It's not right."

Cathryn admitted, "It was wrong of me to use a potion to make you too horny to resist, and I'm sorry I had to resort to that Valeria. I knew you wouldn't do it otherwise, and as I said it was necessary to initiate the transformation. There was only a limited window after drinking the pink potion, otherwise it would have been wasted and you'd be left in your original form."

"But we're family," I responded. "It's not done."

She shrugged, "It's not done because of social taboos, not that that's stopped royalty and nobility from doing it for ages. And if you're worried about me getting pregnant you can relax. I took a potion last week to ensure that wouldn't happen. And now you've got that body there's literally no risk of you getting me or anyone else pregnant anymore, cutie."

Her expression shifted to a smile as she added, "I know you've fancied me for years little sister, I've seen how you looked at me. I love you as much as you love me. And now that it's just the two of us, there's no reason for either of us to hold back."

My eyes widened and my cheeks turned pink, and I had no idea what to say or how to respond. My heart was racing a bit, but I tried to push those thoughts and ideas aside for the moment.

Instead I asked, "Why does it feel like everything's bigger than I remember?"

"Seriously?" she almost laughed. She got to her feet and motioned to me, "Get up, stand here in front of me."

I frowned as I got to my feet, then my eyes went wide as I looked up at her and gasped.

Yesterday I stood a hundred and eighty-six centimetres tall, eleven centimetres taller than my sister. Now I found myself tilting my head to look up at her, and there was a happy flutter in my stomach as everything else suddenly made sense. It wasn't the table and chairs and rooms that were bigger. It was me, I was smaller.

If I had to guess, I was at least twenty centimetres shorter than Cathryn, which meant I was more than thirty centimetres shorter than I was yesterday. I'd be lucky if I stood a hundred and fifty-five centimetres now. I suddenly felt tiny next to my sister, and that left me feeling equal parts surprised and happy.

She giggled, "That's right cutie. Now you have nothing to complain about when I call you my little sister."

"Wait," I said as my eyes went wide again. "Did you know this would happen?"

"Of course I did!" she laughed. "You always used to slouch and slump, you tried to make yourself look smaller. I just gave you what you wanted. Didn't I?"

My cheeks went red and I bit my lower lip as I hesitated.

Cathryn was still grinning as she prompted, "Tell me the truth. Isn't this perfect?"

"Fine," I mumbled as my blush got brighter. "You're right, I do like it. It's hard to admit it though, Cat."

"Good girl," she responded which sent another little flutter through my body. "I think it's time for that last potion now. That'll seal everything else, and ensure all this is permanent."

I couldn't suppress the smile that formed on my lips at that thought. I sat back down at the table and carefully took out the remaining vial. The liquid inside was clear but thicker than water. It had a musky, heady scent but like all the others it was sweet on the tongue. I couldn't place the taste though. It wasn't bad, in fact it was actually quite good. Almost compelling in a way, and I found myself licking my lips after it was gone.

As I put the empty vial back in the case I frowned. I'd just remembered something else from last night, and I looked up at my sister again.

"What was the blue potion? You drank that last night, at the same time you had me drink the pink one."

Cathryn had a slightly smug look on her face as she nodded, "I did. It was a little gift for myself, an advantage to help me with my cultivation and help us both with our alchemy work."

"What sort of advantage?" I asked. "And what do you mean by cultivation, you keep mentioning that."

She still had that smug look on her face as she replied, "We'll get to that later little sister, but I'll reveal some of it to you now. Hand me that blanket you're wearing."

I unwrapped the blanket from myself then handed it over. She carefully folded it up, then she turned her chair around so it faced away from the table.

She sat down again and placed the blanket on the floor by her feet then stated, "Come and kneel here in front of me."

"Ok," I replied as I got on my knees on the blanket right in front of her. I appreciated having the blanket there under me, bare knees on the rough wood floor wouldn't have been that comfortable.

Cathryn smiled, "Good girl."

The words sent another flutter through me, and I smiled at her before asking "So what about the blue potion? What advantage or gift did it give you?"

Cathryn smirked, then she slowly lifted up her dress skirt as she spread her legs. I was still kneeling on the floor in front of her, and my eyes widened as I saw it. And for some reason I automatically licked my lips as I stared. For just a second I thought it was mine, I briefly wondered if somehow she got it when we had sex last night. Then I realized hers was a lot bigger than mine ever was.

"What...?" I asked as I stared.

My sister continued smiling at me, she kept her eyes on me as she reached down and took hold of her new penis. After a couple strokes it was already starting to rise up on its own. I realized her vulva was still there, she still had all her original womanly parts too. It was hidden at first, beneath the cock that was inexplicably hardening between her legs.

I licked my lips again as I caught a musky, heady scent from it and my mouth watered slightly.

It took me a few more moments to find my voice, then I looked up at her and asked "You gave yourself a penis? What in the world possessed you to do that?"

She was still stroking herself as she responded, "I got the idea from my friend Monique at the academy. Her little sister Evie started her first year at sorcery school last autumn, but before she left Monique gave her a similar potion as a joke. Except it turned out Evie enjoyed it, so Monique gave her a permanency potion so she could keep it."

"Anyways," Cathryn added, "The important thing is now that I have both, I'll be able to cultivate both ways."

I gulped, "And I'm going to help with that?"

"You are," my sister nodded. "And I can tell you're eager to get started, so don't hold back little sister."

I moved forward on the blanket so I was kneeling between her legs, and I hesitantly took hold of her thick girlcock in my right hand. It felt hot to the touch, and it was obviously sensitive as Cathryn's body responded slightly from the contact.

Fully erect it had to be nearly twenty-five centimetres long, and it was thick enough my small hand could just barely wrap around it at the base. There was some pre already starting to dribble from the tip, and I used that to get both my hands lubed.

That musky heady scent was getting stronger and I licked my lips once more, then with both hands stroking up and down the huge hard shaft I leaned closer. My lips parted, and I slowly took the tip into my mouth.

"Oh yes," Cathryn whispered. Her hands were at her chest, massaging and kneading her breasts through the fabric of her dress.

I did what I could with my lips and tongue, while my right hand continued pumping the shaft. Meanwhile my left hand dropped down between my own legs, and I found my lower lips were already dripping wet. I'd never even touched a woman before, but it didn't take long to figure out what felt good. I was soon moaning softly as my left hand rubbed up and down along my wet engorged labia, and I paid extra attention to my clit which seemed incredibly sensitive.

Cathryn was moaning as well, louder than me. And I could feel her muscles were beginning to tense, as were my own.

Both my hands moved faster, while my lips and tongue danced over the head of her enormous shaft. I could feel the pressure building within my body, and I could feel it in hers too.

She came first, and that initial surge of hot musky cream nearly choked me. I recognized the taste though, it was like that last potion and I couldn't get enough of it. I gulped down as much as I could, but there was simply too much and I finally pulled back so I could breath. The rest ended up spattered over my face and dripping down onto my boobs, but I was barely aware of it as I reached my own orgasm a moment later.

My body quivered and my eyes rolled back as my mind went blank for a few moments. There was nothing but waves of bliss washing over my new feminine self.

When I finally came back down I was still kneeling before Cathryn, naked and sweaty and sticky. My heart was racing, and I looked up at her with wide eyes and gasped "Holy shit that was amazing..."

"Yeah," she nodded as she stared back at me with a smile on her face and a glint in her eyes.

PurpleCatGirl

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