Happy birthday to me, I thought to myself, grinning ear to ear as my big sister Calliope led me down the dormitory hallway. Pink walls with intricate engravings and shiny white marble gave a feeling of elegance, as if we were walking down a colorful, pastel iteration of an Ivy League school. Calli’s heavy Majestic Shields boots echoed as we walked, puncturing the silence that otherwise befell the dormitory corridor. Unlike the Combat quarters, known for their rowdier Magical Girls prone to partying, fighting, and orgying (as she told me), the Support class girls were quieter. These were the introverts of the bunch, prone to hiding away in their rooms as early as 7 and sitting in front of their computers ‘till 3.

That of course included my big sister Calli, who finally made good on her promise to bring me over for a sleepover in the Majestic Shields dormitories. After she pulled a few strings, given it was rare to bring a family member in, she said. Unless you were a high-ranking member, or otherwise an important part of the group.

“And here we are, last stop on the tour.” My sister pulled out a key card and pressed it against a metal surface, opening an oak brown door. “My quarters.”

I followed my sister in and closed the door behind us, dropping my overnight bag on the floor and kicking off my sneakers. Calli bent over and seamlessly slipped her metallic boots off her feet, picking them up and dropping them upright with a violent thud.

Really, how much could a Majestic Shield’s boots weigh?, I thought as I watched Calli plop them down. On r/MajesticShields, most fans assumed they were only 10 pounds. Maybe a dozen most. But to my surprise, their armored exterior looked so thick up close. I presumed they could crush my hand with ease if Calli accidentally dropped one on me, let alone stepped on my fingers. And Calli wasn’t even a Combat class member. Imagine if she was packing some serious strength.

I was less surprised to take in Calli’s living room, a relatively spacious common area that looked less than lived in. Not much on the white plaster walls, minimal furniture around what looked like a Shields-provided couch. Just a TV, an IKEA stand for it, some game consoles, a cheap brown coffee table, and an old rug to sit on underneath it all (which, admittedly, looked like it needed to be vacuumed). A thin coat of dust rested on the stand for her TV, with only bits and pieces of spotless real estate, like where she kept her gaming controllers. And her VR headset, that thing looked pristine too, admittedly not a big surprise either.

“You live here all by yourself?” I asked.

“What gave it away?” she laughed. “Lack of posters?”

“Yeah, it’s a little bare. No offense,” I paused. “I thought Majestic Shields don’t live in singles.”

“Usually we have a duo if you’re rank and file,” Calli said, shuffling around the house, turning on lights, “but they gave me special arrangements because of my social anxiety.”

“Oh.” Right, that made sense. “That’s nice of them.”

“They’re pretty accommodating,” she continued. “Most of my role is just keeping the infrastructure online, so they even let me work from home sometimes.” She quickly marched deeper into her apartment toward the bedroom, motioning to follow. “C’mon, no surprise that the living room isn’t interesting. I’ll show you my PC setup. I know that’s the thing you really wanted to see here first.”

A narrow, dimly lit hallway led to Calli’s bedroom. I followed her at a distance, watching her red skirt swish and sway with every step. It still felt weird seeing my sister in uniform, let alone one so tight around her body. Up until now, it was impossible to imagine her wearing anything other than graphic tees and comfy shorts, still her choice of wear even when she came home for the holidays twice a year. The Calli I knew, the one I grew up with and saw during break, she still loved sleeping in her Otakon 2006 official t-shirt, playing Team Fortress 2 until 3am, and binging yuri anime with her polycule (read: trans girl harem) while downing instant noodles.

This Calli, the one that invited me to see the Majestic Shields front and center, she was so different in every way. No baggy clothes, no uncombed hair. Form-fitting armor that hugged onto slim curves, black stockings that showed thin thighs and petite calves. A woman that would swipe any girl off her feet, and I mean any girl. Yes, my sister was as thick as a stick, but the Majestic Shield uniform made her look graceful, pretty, curvy, beautiful. And I didn’t know how to feel about that.

Calli held the door for me, beckoning me forward. “C’mon in, it’s not that different from back home,” she said. “Check out the triple monitor setup.”

A large bedroom with a dedicated gaming desktop setup greeted me, complete with a high-end mechanical keyboard and wireless esports mouse. That was the first thing I noticed. The second was the slight musky smell. Yep, my sister alright. She might look strikingly beautiful as a Magical Girl, but she’s still a NEET, through and through.

“Oh,” she said, looking me over. “Is something off?”

“It’s just a little, um,” I muttered, “stuffy in here.”

“Oh? Oh!” She blushed. “Sorry! Can’t take the -cel out of the femcel. Let me take care of that.”

Calli raised her palm, laid it flat, and swirled a few fingers. Suddenly, a light purple flower arose from the center of her hand, followed by a slim green stalk raising the petals upward. The flower grew brighter and brighter, and with it, the smell slowly faded, receding until it was completely replaced by a refreshing lavender fragrance.

“How’s that?” Calli asked. “I know it’s your favorite.”

The scent filled my nostrils, drawing me in. My, that was so pleasing. So lovely. And all through Calli’s fingertips. I looked up at my sister in wonder. “You can do magic around me?” I asked. “That’s really cool!”

“Well, we’re in the Shields’ quarters, so yeah. It’s different,” she said. “I’m allowed to do that kind of stuff around you. I mean, as long as you don’t go blabbing about it on your blog.”

“My blog?”

“I hear you’re a cosplayer or something.” She paused. Her tone suddenly shifted, a dour, heavy look on her face. “I’m sorry to hear about your friends by the way, Kyrie. What were their names? Marisa, Yuna, Lilly?”

How thoughtful. I was a bit surprised, and maybe just a hint creeped out, that Calli knew all three. I assumed she wasn’t even aware of my crossplay tendencies, given I went to great lengths to hide it from my Twitter. But Calli always showed her love a little intensely.

“You’ve really been keeping up on my online footprint, huh?” I said sheepishly. “Yeah, it’s really scary, they just disappeared out of thin air. One by one. And the police are as useless as ever. The GoFundMe we put up to raise money for a private investigator had a great first night, but we woke up the next day to find it suddenly taken down. Probably because of internet trolls hating the kind of, um, cosplay we do.”

“That’s a shame. Yeah, your photos seemed a little crossplay-ish.”

“Uh, yeah, that.” I gulped. “Just for fun.”

“I don’t judge.” Calli smiled at me, and I felt my face burn red. “I really hope they turn up. These things have a way of coming out for the best.”

“Yeah, right. Thanks, sis.”

Oh, Calli. Awkward as ever. But you can’t fault a sis who has her heart in the right place, right?

A beat passed, quiet between us. Calli scrunched up her face, growing less serious, instead looking like an excited and eager puppy.

“On a lighter note. Now that we’re in my room—presents!” she giggled. “I have two big ones for you. Well, technically three, since you got the mini-tour and you’re sleeping over tonight, but that’s just a minor thing. Compared to the two really cool stuff I’m about to show you.”

“Yeah?” My eyes lit up. “What did you get me?”

“Okay, first. I’m trusting you. You’re like a little deputy Shield tonight, Kyrie, so you have to honor your share of the bargain.” My heart leaped in my chest. I felt like we were kids again, roleplaying Magical Girls and Monster Boys in the backyard. “I’ll show you some super cool Shields stuff, but you can’t tell anyone. Not even Mom and Dad, and definitely not Reddit. Promise?”

“I promise, trusty Shield,” I said. “Honestly, I’m just excited to get to see you at work.”

“Well, it’s the least I could do for my little brother on his 20^th birthday,” she giggled. “Trust me, I want this to be a night to remember. 20 is a big deal!”

Calli placed a hand on my arm, looked me in the eyes, and smiled.

“My little Shield,” she said softly. “I just want you to know, I love you so much. You mean the world to me. I don’t know what I’d do without you. And even though I don’t get to see you much, I want that to change before another girl snaps you up.” She leaned over, close to my neck, and briefly sniffed me. Twice. Then three times. “Oh, and you smell really nice. Like a girl.”

“Oh.” I paused for a second, completely unsure how to respond. Calli looked at me as if everything she said was normal, appropriate, and not really fucking weird to say to your brother five years your junior. Even for Calli, this was kind of bizarre. “Um. I love you too?”

Calli’s hand stayed on my arm, then she gently pulled it away, still beaming. Her fingers briefly made contact with my bare arms before gracing my stomach, which made shiver.

I felt bad, at first. But what’s worse, I quickly realized how soft and gentle my sister’s skin felt. And warm. So very warm. I remembered her hands feeling patchy and dry growing up, fingers chapped from neglecting lotion when we ran the heater during the winter. But now? Again, truly lovely to the touch. A touch we rarely felt to begin with, as even during the nearly two decades we spent living together, we rarely made personal contact. Not since we stopped roleplaying as kids, anyway. We just weren’t a touchy-feely family.

I shuddered and tried not to think about all that too hard. Calli is Calli, awkward is her middle name.

“Okay, let me show you something cool.” She quickly broke eye contact, scurrying over to her desk. Finally, relief. “Sit on the bed, and watch your big sis get to work.”

I plopped down on her queen-sized bed, rather large for someone so slim, but certainly comfy to the touch. Not something that particularly caught my attention otherwise, though. Instead, I watched as Calli stripped off her armored gloves (which tumbled to the ground with a loud clank), plopped down on her Herman Miller, turned on her computer, and began typing furiously on her mechanical keyboard. Soothing white noise filled the air from her desktop’s fans, along with RGB lights in the lesbian colors. Not a surprise. Clicking and clacking, clicking and clacking, she kept typing away as all three monitors whirred to life.

Calli swiftly inputted the password for her encrypted computer, groaned as she waited for the login screen to disappear, and then entered a string of commands into the full-screen terminal that popped up.

“Woah, is that a command line interface?” I asked. “What are you running, Linux?”

“Sort of. It’s my own distro, and it makes installing Arch look like a breeze,” she said. “Guess who I named it after?”

“Who?”

“You.”

I blushed. “Really?! What??”

“Your first birthday gift, a special part of Majestic Shields history. Forever!” she giggled. The CLI disappeared, and instead a white loading screen popped up with a blue bar gradually creeping upward. “Introducing... Kyria 1.0!”

“That’s so cool, I—” I caught myself. “Wait, Kyria? Why Kyria?”

Calli kicked her feet back and forth and snickered like a schoolgirl. “I just thought it was more fitting for you! Sometimes you’re more like a ‘Kyria’ than a ‘Kyrie,’ like in your crossplay photos. Hehe!”

“Oh.” Calli being Calli. “Um, well, I suppose that’s cool.”

A desktop GUI whirred to life, spitting up two rows of icons and a manga illustration as her wallpaper (again, not a big surprise). I recognized immediately shortcuts for Team Fortress, Left 4 Dead, Morrowind, and Fallout: New Vegas. Good to see Calli is getting gaming time in, I guess.

And then I saw her background. An anime image of a Majestic Shield, binding another Shield with rope, her hand sliding toward the bound girl’s skirt. The “victim” was curvy and feminine, with perky round tits and supple thighs. Oddly enough, the tied-up girl seemed to have a visible bulge pressing into her skirt’s fabric, comically so, leaving little to the imagination—like a futanari doujinshi, over-the-top and entirely unrealistic in every single way.

My gaze turned to the perpetrator, who had slim thighs and a lanky build, looking almost like a nerd girl who couldn’t help but perv on her futa friend. If I didn’t know better, I’d say she looked suspiciously like my sister, but it was all just a coincidence.

However, I knew better.

“That’s… um. Wow, did you have that commissioned?” I asked. Calli beamed at me as the futa image burned into my retinas.

“Pretty cool, huh?” she said proudly.

“Uhh.” I looked at the bound girl on the screen. She was rolling her eyes back in sickly-sweet pleasure, clearly loving the experience despite its S/M overtones. The orange and pink RGB lights shined brightly in my face as I gazed back at the drawing, feeling like a kaleidoscope of sickly sherbet ice cream had invaded my peripheral vision.

And then I noticed something else. Three dots under the short-haired girl’s left-hand eye. My hand went to my face, and I touched the three raised bumps on my own cheekbone. That was my birthmark. Mine.

“Calli?”

“Yes!” I heard her suppress a muffled laugh.

“Is… that… is that Majestic Shield supposed to be me?”

“Aha, you figured it out!” My sister squealed and giggled like I had just won a long-planned game of Hot & Cold. “I know you always dreamed of being one when we were kids! Well, here you go! Ta dah! It’s just like our roleplays back in the day, only we’re both Magical Girls. Now I get to think about you all the time when I go to work!” She smiled widely, kicking her feet in the air again and again. “Do you like it?”

“Umm.” The color drained from my face, and I felt a pit drop in my stomach. We did play with rope a lot as kids. And sometimes I did pretend to transform into a Magical Girl, and she would also be a Magical Girl, and… oh God, maybe Calli had the wrong idea about playtime all those years ago. “Don’t you think this is a bit much?”

“Don’t worry, it didn’t cost too much money. One of the Support girls here is a hentai artist in her free time, so she did it for me on discount!” She proceeded to ramble on, zooming in to the illustration, pointing out every intricate detail of the Majestic Shields uniform’s depiction on the futa girl, down to the finest replication of light, metal, and texture. “And yes, a bulge like that would not necessarily appear, but the disturbance in the skirt, incredibly realistic!” She declared proudly. “See? Only the best for my little sister!”

I stood with my jaw agape. “Did you just call me your little sister?”

“Oh, whoops, I’m getting ahead of myself. This is only half of your birthday gift.” Calli seemed just as chipper as ever, as if she was completely unfazed by the sheer inappropriateness of the last 15 minutes. “I didn’t just build you an OS with a little illustration for you. I made something else too, with lots of blood, sweat, tears, and just a little more. Watch!”

My sister turned around to her desk, reached for her mouse, and popped open a command line terminal. She quickly typed in a few words, clicked enter, and gave me a wide, toothy grin.

“Happy birthday!”

The ground shook. An enormous, whizzing sound arose from under Calli’s bed. Two metallic arms shot out from each side and gripped my wrists, drawing my limbs apart and dragging me all the way to the headboard. Shackles jutted out from the edge of her bed, seeking my ankles, and locking tight against the bare skin between my socks and jeans cuffs. The two structures quickly coordinated together, as if perfectly programmed to bound a captive—stretching me out, forcing me to lay entirely flat on my sister’s bed.

With my head staring at the ceiling, arms at perfect 180 degree angles, and ankles spread just enough to create a v-shape, I felt ridiculously exposed. And trapped. So very trapped.

“Calli!” I screamed. “What the fuck has gotten into you?!”

My older sister’s laughter grew louder, growing from playful giggles into boisterous cackles. “You want to know what your gift is?” she said. “I’m going to turn you into a Majestic Shield!”

My heart leapt into my mouth, and my skin ran cold. “You’re going to do WHAT?!”

Despite my panic, Calli continued typing away at her computer, snickering to herself, code after code filling her monitors. Her window curtains closed by themselves, the door slammed shut and locked itself, and a low, soft, droning hum filled the room from her mounted speakers above. The sound penetrated my ears and soothed my brain, and I suddenly felt drowsy, weak, struggling to think straight. Thick, metallic rings locked around my chest and thighs in an instant, securing my submission, while white, nimble steel wires placed a pink collar around my neck, then locked it shut from the back.

Typing, typing, typing, with every click and clack of Calli’s fingers, my heart pounded against my chest, begging for release.

“Calli! This is crazy!” I shouted. “I’m a boy, I can’t be a Majestic Shield.”

“Well, that’s two problems we can fix, so I guess you’re technically getting four presents this year,” she said, happily humming to herself. In a matter of seconds, my sister quickly finished typing and pushed her seat away, letting the code run. I looked up in agony and fear as she towered over me, demanding my full attention with her innocent, playful gaze. Her hands behind her back, eyes glowing, smile cheek to cheek, she paced around the bed, looking me over like a specimen to experiment on. Or a creature to dissect.

Or a sister to roleplay with.

“You’re going to be my finest work yet,” she said, pride in her tone. “Years of perfection, boiled down to the most minute detail. Tonight, Kyria, you finally turn into my beautiful baby sister.”

“Your little sister?!”

Calli reached out her bare hand and grabbed my cheek. Her palm’s soft, gentle texture unnerved me as she tried to soothe my skin, my big sister’s awkwardness now revealing itself as something far more sinister. “Yes, that’s what you are,” she explained. “My precious little girl!”

I tried to squirm, I tried to push back against Calli’s touch. But the restraints held me so tightly in place that I could barely budge. And even if I wanted to fight back, the white noise seemed to have a soothing effect. A tiring effect. I felt something warm and fuzzy resonate from the pink collar on my neck, and my muscles relaxed, my eyes growing heavy and sleepy.

“What are you doing to me?” I whimpered. “I’m struggling to stay awake.”

“Oh, how I’ve been waiting to see you like this.” Fingers trailed along my face, soft and gentle, but occasionally gripping onto my hair or skin, sizing me up. “I don’t work with infrastructure, Kyria. I lied to you. I work with our most important recruitment drive in the history of the Majestic Shields. Feminization. Mandatory feminization. And I’m our lead engineer.”

Calli leaned over me, running a hand across my t-shirt, wandering down my belly. Sweat rolled from my brow to my cheek as I watched my older sister lift my shirt, fingers tracing along bare skin, tugging on my belly button. “So much pretty flesh to work with,” she whispered to herself, drawing my navel into a thin line. “I’ve always wanted to see you tied up like this. Oh, how excited I got looking at that commission as it came together.”

“You’re really creeping me out,” I cried, trying my best to maintain a sense of dignity. “I want you to let me go and delete that thing immediately.”

As if purposefully ignoring me, her hand crawled further up my body, testing my pecs, pinching my nipples. “Will you be an A-cup, or a C-? Will you look even smaller than me, or will you put your own big sis to shame?” She giggled to herself as I winced. “I hope not.”

Her free hand slipped under her skirt, and I watched the heavy fabric rustle against her knuckles. “I want you to be beneath me, always. In every single way. Because that’s how it should be, big sis and little sis.”

I closed my eyes and gulped. A wet, sloshing sound filled the air as my sister whispered my name. I was a virgin, but I knew what she was doing, I knew that sound. Even with my eyes shut, I could tell her fingers were deep in her pussy, pressing in and out, playing with her soaking wet cunt as she thought about what I was about to become.

Another moan escaped her lips, loud and greedy. I shivered as I felt her squeeze my arm.

“Open your eyes,” she cooed in a sing-song voice.

“I-I don’t—”

Her hold on me tightened. “Do it.”

“I don’t want to, Calli.”

“Then I’ll make you do it,” she snapped.

A sharp, suffocating death grip surrounded my arm. I opened my eyes in terror, expecting to see a heavy metal cuff pulling at my limb. But there was no extra bondage added to my body, no additional machine brought out at all. Instead, all I saw was my sister’s hand. Her bare hand. Fingers clenched around my forearm, her bicep barely taut. I could feel my circulation struggle, threatening to turn blue. Did Calli have the capacity to break bone underneath? To shatter it into an unrecognizable mess?

I looked up at my sister. Eyes beady and annoyed, a smirk played across her face. “This is barely a workout to me. How does it feel for you?” she asked. I yelped as a thick, back bruise spread across my skin. “Not good, no?”

“Please don’t hurt me Calli,” I pleaded, stuttering.

“Are you gonna be a good girl?”

“I will,” I begged. “I-I’ll look at you. I’ll do it.”

“Good.” Her grip loosened, and my arm screamed in pain. But at least it was safe, angry black and blue bruising aside. “I’d hate to see you ruin your big day.”

Calli lifted her legs and got up on the bed, the entire mattress briefly tipping forward thanks to the sheer mass of her uniform’s armor. Slowly, the bed frame whizzed and whirled, adjusting for my sister’s added weight. As it stabilized, Calli lowered herself over onto my thighs, her red skirt hovering above my upper legs. I watched as she drew closer, fingers digging back into her cunt, slowly moaning my name again. With her free hand, she tugged onto my pink collar, as if preparing to do something with it.

I squirmed in fear, and to my horror, I glimpsed under my sister’s skirt. I couldn’t quite make out my sister’s pussy, but I could see her knuckles working her fingers inside her, back and forth. My body was dangerously close now to Calli’s pussy for sure, far closer than any brother should ever be. And what’s worse, my sister was aroused. Very aroused. Small wet droplets dribbled from her fingers, staining my jeans underneath. I looked down to assure she hadn’t made a royal mess across my clothes, only to find another horrific sight: My cock straining against my jeans, begging for freedom from its denim confines.

“Oh, look at that,” Calli whispered, leaning over to look down. “Is someone excited about becoming my little sis?”

“No!” I said, my face turning red.

“But it’s your dream, isn’t it?” she teased, eyes peering into mine as she fingered herself. “Didn’t you used to cry yourself to sleep at night, wishing our little Magical Girl roleplays could come true?”

My cock throbbed in my pants. I felt hard. So very, very hard. “Sometimes boys just do that!” I said. “I never actually wanted to become one. Not as an adult, anyway!”

“Nuh uh.” Calli giggled. “I know everything.”

“Shut up!”

“I mean, I do though. I truly know everything,” she laughed. “Tell me. What do you think happened to your crossplay friends? What were their names again, Marisa, Yuna, and Lilly?”

“What?! Did you have something to do with that?”

“So curious their GoFundMe just magically disappeared! I wonder why?” Calli snickered, grinding her pelvis against the heel of her hand, as if my anxiety itself was a point of arousal. “Here, baby girl. I’ll pull out, and you just watch.”

Calli slipped her fingers out of her pussy. Still dripping wet, she drew the outline of a pink heart and blew a kiss into it.

A portal opened immediately, and I saw an image of my friends appear. My three crossplay friends. Unmistakably them, still thin and slim, safe and sound as ever. Their feminine bodies leaned over a table sipping drinks, almost as if they were relaxing after a long day at one of the cons we’d always hit up.

But they weren’t dressed in maid outfits or anime cosplay this time. No. Red skirts draped along their legs, black stockings tight around supple thighs. White, shiny, form-fitting armor clasped onto their bellies and chest while they talked to each other happily and eagerly. Those faces were unmistakably theirs, but different. Rounder. Softer. Plumper than ever. Even their lips looked so much fuller, some even wearing high-end makeup. And their eyes, my, how they sparkled wide with joy.

My eyes lingered to their breasts. Once flat chested, even with padding. Now? Their breasts were round, full, voluptuous, filling out their armor perfectly. It was as if their very bodies were made to entice and attract others, down to the last curve. There was no way that this was Shields cosplay; their beauty was exemplary, and besides, the material was too lifelike. It was simply impossible to wear something so heavy and form-fitting with padding, the look would be all wrong.

No, there was no mistake about it.

“They’re… Shields?” I watched in awe as Marisa whispered something into Yuna’s ear, and leaned close together, eyes locking.

“Now they are, sister.” Marisa and Yuna cupped one another’s cheeks and began to make out passionately, eagerly. Calli smirked, and I realized I was leering; she quickly poked the portal and made it disappear back into nothing, the image rippling away as the magical heart faded from existence. Almost as if she was denying the opportunity to entertain my curiosity.

“How do you think I perfected the feminization technique? How do you think I tested everything I wanted to do on you tonight? Your friends were the perfect subjects. Eager, obedient, similar to you, and best of all: Only mildly hesitant at best,” Calli bit her lower lip and gave a soft moan. “And in return, they gave me all the information on your private life that I ever would have wanted. All to confirm, for sure, that my plan would succeed.”

“That’s sick!” I cried. “You turned them into girls, and are they even… happy?”

“I don’t know, they looked pretty happy to me, don’t you think?”

True, they did look like they were having a great time. Even as it came out of my mouth, I knew that argument was pretty pathetic.

“Poor worried Kyria,” my sister cooed, “scared of your own desires, even though you’ll live your secret little life online.” I watched as Calli’s hand crawled up across her thigh again, working toward her pussy, which was now a hair-length away from my bulge. “What’s this about running a modeling site for those crossplay maid outfits? Posing with other girls?”

I winced. “Yuki is just a friend!”

“Naughty, naughty. Looks like someone’s showing off her pretty bulge to another girl instead of me.” Calli thrust her pussy against the heel of her hand again, grinding on its hard surface. “And what’s all this about wearing panties underneath your jeans? Congratulations on your little birthday fundraiser for Magical Girl-themed lingerie, your fans must be sooo happy! But my, my, you leave a post up like that, and someone is going to start getting ideas. Like your big sis in the Majestic Shields.”

I bit hard onto my inner cheek, so hard I drew blood. Calli’s hand reached for my jeans button, undoing it with ease, drawing down the zipper. I instinctively raised my arms and legs, trying to protest my sister’s lewdity, but what was there to do in my shackles? My ankles and wrists could barely budge. And I felt too tired from the reveals, the strange droning sound, the ridiculously painful bruise my sister left on my arm, and the soothing collar’s pulse as it relaxed my anxious limbs. No, there was nothing that could be done. Nothing.

So as Calli tugged on my waistband and lowered my jeans, I accepted my fate for what was about to come. For what was about to be revealed by the red-and-white panties underneath, complete with a little red bow on the top.

“Official Majestic Shields panties!” Calli laughed. “Wow! These literally just came out! You little perv!”

I pulled my head away, blushing. “It doesn’t mean I want to be a girl. O-Or that I like you as anything more than a sister!” I stammered pathetically. I quickly decided to look back at my sister, just in case she tried to use her intense strength on me again. “I like being a boy!”

“Do you?” Calli pulled my jeans down to the metal cuffs around my thighs, eyeing my throbbing cock. Its outline was unmistakable in my panties, nearly straining the fabric, the tip threatening to peer out any moment. “Because your cock is telling me otherwise.”

“No!”

“I saw your search history over Christmas.”

“Creep!”

“Desperate, pathetic Kyria, gooning to all that siscon yuri.” I froze. My sister’s finger hovered inches above the tip of my cock, threatening to touch it. “Here’s a little tech tip, sis: If you’re going to read My Sister Turned Me Into a Magical Girl And Now She Wants to Peg Me!, you should at least use a VPN. Otherwise I might start commissioning scenes inspired by your favorite manga.”

I gasped. “How dare you!”

“Aww, and did my baby sis Kyria keep going to the Otokonoko page to buy estrogen with crypto, then chicken out last minute before she typed in Mom and Dad’s address?” Calli pressed her cheeks between my thighs, resting her soft skin against my hairless legs. Her mouth was so close to my balls now, I could literally feel her warm breath on my undercarriage. “Poor little Kyria,” she cooed in a mocking sing-song voice, “sending late night messages to Marisa, worrying how estrogen will make her so soft and pretty.”

“I-I was just a little curious! And besides, I mostly wanted it for the packaging!” I cried, squirming from the wet, hungry moisture enveloping my crotch from my sister’s moist breath. “It’s got cute femboys on the box! I wanted to use it as inspo for my crossplay!”

“If you really wanted to be a girl that badly, you should’ve come to your big sis ages ago. No pun intended,” she giggled. “If only you knew. I could have offered you quick and easy feminization in a matter of seconds. Why, if anything,” she said, hand digging between her thighs, stroking her pussy, “I’m doing you a favor by kidnapping you here, and turning you into the pretty girl you were always meant to be.”

Calli looked up from my bulge. Our eyes met, and yes, the possessiveness, the perviness, the creepy leering attitude, it all was there. I could see it all in those hungry little pupils of hers. But then her eyes widened. And something else grew across her face. Like pity. Like sympathy. Like care. Like… love. Maybe in her own twisted way, Calli wanted what was right for me. And maybe this was her way of showing me that, weird as it was.

“Look. I know you want it.” My sister gulped, and I could hear her breathing quicken. “And I can’t let you leave this room without getting it. Whether by your choice, or mine. Because I love you, and my world would shatter if my baby sister spent the rest of her life a miserable shell of herself.”

“I…” I could hear Calli’s slick wet pussy gush against her fingers. My cock pulsed so hard it began to lift the edge of my panties. “Well,” I muttered. “How does it work?”

I felt the grip tighten on my pink collar. “I call on the Goddess to empower me to shape you,” she said. “But instead of using magic to carefully and delicately sculpt your body, She does the hard part. With my touch, every part of you will turn you into a perfectly feminine version of yourself, designed to the Goddess’ specifications. Her beautiful, irresistible specifications.” Calli gave a long, loving sigh, her warm breath flooding my bulge and teasing my hard red cock underneath. “As long as the droning hum plays, our privacy remains, and you stay bound, the ritual will be successful. You’ll become a Shield.”

“Okay,” I said. “Well, actually, that’s… not too bad.”

“Wait.” My sister rose her dripping wet hand from her pussy. “There’s one more thing, it’s the most important of all.” She paused, took a deep breath, and cleared her throat. “The transformation will only be temporary unless the Shield and the candidate share a special bond.”

“Like, the two of us being sisters?”

Calli shook her head. “No. I’m talking about a ritual bond. Which means we need a fluid.”

“Uh.” I paused. “What fluid?”

“You know, the greatest fluid of all. The life fluid. The most important one you can possibly ever give or receive.”

“Gatorade?”

“What? No. I have to take your seed into my womb.”

My entire body froze. “My… seed?”

“Yes,” she said, nuzzling her face against my thigh. “You need to breed me with that delicious girlcock of yours.”

My face burned red. Any drowsiness that once overcame me started to fade. I watched as Calli looked into my eyes again, then drew her head between my legs, letting out a sheepish giggle like a schoolgirl that had just confessed her crush to her best friend. It was weird. It was strange. It was pretty bizarre, even for a girl who spent most of her social time on Discord.

And yet. Even as my anxiety grew in my chest. Even as my heart thumped with fear. Even as shame swelled in my head. Even then, my cock began to poke out of my tight white panties and push my red bow upward. Even then, I arched my back and moaned slightly, unable to help myself.

You see. Deep down, somewhere, somehow, some part of me was a girl. A girl who wanted out. And also wanted to fuck my older sister.

“Oh, little sis,” Calli cooed, her face flushed pink, “won’t you please fill me up? I always thought you were so pretty, but now that I know you’re meant to be a girl, I want you inside me so badly.”

“Calli…”

Her free hand reached for mine. It was wet and damp in her own juices. But her grip wasn’t hard, rough, or threatening. This time, it was oddly tender. “Kyria. I love you so much.” She burrowed her face into my thighs and took a long, hard drag, sniffing the musk seeping from under my panties. “You already smell so feminine. I want to ride you so badly. Let me do it, let me take your cum, just like I’ve taken all of your friends’ already. Let us become more than sisters, but lovers, bound by the Goddess’ pact.”

I couldn’t take it anymore. My panties slipped. My cock stood fully erect, eager and at full mast. I squirmed at first, anxious at the thought of my own sister taking my virginity. But as Calli’s moist hand squeezed my own, I felt something grow beyond panic. Beyond fear. Love. A gentle, wholesome love. And with it, a feeling of hope, of promise, of a path forward beyond, what? Hiding in my room all day, pretending to be a maid for girls on the internet?

I looked down at my big sister, her face still burrowed inches away from my exposed dick, and some part of me began to give in. To wonder what it would be like… to be inside my older sister. The hikikomori who shared her hobbies with me, the lesbian who made life work for her despite all of her hardships. Who was well liked within her polycule, and always accepted me as the boy that wanted to be a Magical Girl.

Maybe something had made her love a bit sick and twisted, a little perverted. And yes, not without its violence. But damnit, wasn’t it still love? Didn’t she want what was best for me, even if she had to force it on me?

“Alright, Calli,” I whispered. “Take me.”

She lifted her face from between my legs, eyes wide and eager. “You mean it?”

“I-I’m yours.” I thrust my pelvis ever so slightly, revealing my exposed cock. “Turn me into a girl. Make my dreams come true.”

My sister stared at my erection, eyes transfixed with hunger. Slowly, she crawled along my body, over my chest, draping her armored form above me. It dawned on me that Calli had enough weight on her chest and torso to crush me into paste, but she refrained from asserting any more power than she needed to. Instead, she held her composure, leaning over me, licking her lips as she held my pink collar tight.

“I love you so much, Kyria,” she said. “I know this is right for you. I know this will make the best birthday gift for you, ever.”

“I hope so,” I replied.

Calli arose, as if about to straddle my belly, unbuckling her breastplate with her free hand and throwing it aside. The heavy metal slammed on the ground with a dull thud, which reverberated through the room before fading into an echo.

My sister was fully exposed now, with just her red skirt hiding her pussy. And for the very first time, I saw her bare breasts in their entirety, arched forward for me to stare at in all their glory. Her tight black seethrough leotard hugged onto her chest, perky tits rising up and down as she heaved with excitement. The Shields undergarment, thick with protective nylon, just barely contained her pointy nipples as they protruded outward with arousal. My eyes wandered downward as I watched her fingers drag along her slim belly, enticing my gaze as her tummy rose and fell with each breath.

“So, what do you think?” she asked. Her hand graced her breast, squeezing it softly, teasingly. “Puberty treated your big sis well, right?”

“Yeah, it did. You’re so beautiful,” I whispered. “Will… I look as good as you?”

“Definitely,” she said. “In your own way.” A hand slipped under her skirt again, playing with her pussy. “I’m still so wet,” she whispered. I heard her stockings unzip from her leotard, and she pushed them down across her legs, exposing her bare skin, which looked smooth and feminine under the low light. “I can’t wait any longer, Kyria. I need you.”

“I need you too, I think,” I whimpered.

“Then let me take you.”

Calli slipped her skirt to the ground and slid her leotard to the side of her crotch, then gripped my collar and tugged my head and torso slightly forward. I looked down at my sister’s pussy in amazement, a thick untamed bush slick with wetness, a hidden and mysterious part of Calli I never imagined I’d see in all my life. Slowly, my sister leaned closer to my cock, pussy lips ready to receive me as her free hand gripped onto my chest.

“It’s about to start,” she said. “Are you ready?”

“As ready as I’ll ever be,” I told her.

“Let’s do it then.”

Slowly, a warm, wet embrace enveloped the tip of my cock. My sister gently lowered herself onto me, moans escaping her lips as she pressed my head into her pussy. Second by second, she took me in, enveloping me, capturing me. She closed her eyes and cried out in pleasure as she took in all of my head, swallowed up by her ravenous cunt.

And then she lowered further. Further. Further. Until my shaft began to disappear within her, taken by her, filling her, surrounded by her.

Oh, Calli. God, how she felt so good. So moist and smooth, so warm and inviting. Is this what pussy felt like?, I asked myself. Is this what everyone was obsessed with? Because getting it from your sister felt… amazing.

“Oh goodness,” I said. “Sis…”

A whimper escaped Calli’s lips. “You feel so good, Kyria. You make me feel so full.” Slowly, she lifted her hips back up, climbing up my cock before sliding down onto my shaft again. She bucked against me, flexing her pelvis, as if every inch of her pussy was sizing up my throbbing cock inside her. Again, she lifted up and lowered downward, her bobs growing faster, quicker, more rhythmic. One hand gripped harder onto my collar while the other dug into my chest, as if relying on me to balance herself as she rode me, using her athletic prowess to slide her cunt up and down, up and down, up and down my slick hardness.

I knew I was fucking her. I knew I was breeding her. But I didn’t feel like I was the one in control here. I was being ridden. I was being tamed. I was being made into her own. And oh, how good it felt. How sick, but how so very sweet, to have your sister take your virginity from you.

“It’s time,” she said, bouncing up and down. “We have to start early.”

“Do it.” A moan escaped my lips, interrupting me. “Before I change my mind.”

Nails dug into my skin. I winced in pain, but my cock only throbbed harder in my sister’s pussy. Calli yanked on my pink collar, tugging my head just a little closer to hers. But even though the ritual was about to begin, she refused to stop fucking me. No, she only pounded down faster onto me, splashing wetness across my crotch and thighs, keeping me red and erect for her cunt. Her moans disappeared, and instead she closed her eyes, focusing her energy on riding me—and preparing for what was about to come.

“Goddess. You who has generously blessed us with Her path for humanity, who has protected us from the forces of evil,” Calli proclaimed. Her face looked serious, as if the world hung on every single word she spoke. “May You bestow Your power to me. May You make me Your Shield, Your Sword, Your Acolyte. And may You allow me to convert this one into Your Majestic Shield, if You find her worthy of Your will.”

White and red sparks flickered from my sister’s hands, igniting into fiery balls of pink flames. I instinctively drew back, but Calli kept my head raised from the bed. The flames danced across my sister’s hands as they rested on my chest and collar. Warm like a fire from a hearth, yes, but not hot. Tingly and fuzzy, but not stinging with burning pain. It was soothing, relaxing, even if strange.

My sister kept her eyes closed as she held onto me, her pussy working faster on my cock. I looked down at her riding me, and that’s when I saw a third light spark from Calli. Not from her hands, but from her womb, where bright pink flames flicked and licked at the surface, soothing and caressing my shaft as she lifted her hips up, drew herself to my tip, and then slid back down again.

“Oh Calli,” I whimpered. “Y-You’re burning me up.”

“Good, sister,” she said. Her voice sounded different. Calm, peaceful, but powerful, reverberating throughout the room with an otherworldly echo. She slowly opened her eyelids, and I watched in awe as pink light shined from each sclera and pupil, light blue irises just barely visible against the brightness. “How do you feel, little Kyria?” A serene smile crossed Calli’s lips as her pussy worked faster and faster on my cock, as if she had reached a sense of calm.

“I… I don’t know,” I said, crying out as her shining womb enveloped me again. “I feel really good inside you.”

“Do you feel warm and comforted?” she asked in a soothing, motherly voice. “Around your cock? Around your chest?”

“Well,” I said, “yes.”

“Look down at your torso.”

The pink flame on Calli’s hand raged, but her palm no longer stood on a flat, even surface. Large round hills protruded from my chest, raising my nipples at their apex. My areolas’ texture, once flat and thin, grew softer, rounder, puffier, and more pronounced. I arched my back as little as I could and watched my breasts jiggle and move, every little motion reverberating through the fat in my growing tits. A soreness grew in the center of each breast, ebbing and flowing, sometimes painful, but then it would die down just as quickly as it came.

“My nipples hurt so much, but I… I have tits,” I said, stunned. “Holy shit.”

With my hands still restrained, I caressed each palm with my own fingertips and, to my amazement, realized my skin had turned completely smooth as well. Thin, gentle, even warm to the touch. To think my skin was once coarse and thick, and now? Soft with a pillowy texture.

“That isn’t the end. My womb, Kyria,” Calli said in her serene tone. “What do you see me riding?”

I gave her a puzzled look. “Still my cock, no?”

“Look closer.”

Yes, of course, Calli was riding up and down my cock. But beneath the dripping wet slickness from my sister’s cunt, my shaft looked shinier, softer. It was as if the skin was thinner and more sensitive, letting me feel every single drop from my sister’s wetness, every single squeeze from her pussy. I moaned as I realized the range of sensation I could now feel with my cock, each and every stimulus far more powerful than ever before. Yes, I didn’t look quite as hard, and my girth had shrunken slightly. But I was still firm, still erect, and still filling my sister’s pussy well, all while feeling every single inch of the gorgeous folds within her.

“That’s incredible,” I gasped.

“Keep looking.”

Calli rose her hips high, athletically drawing herself off my tip, just long enough for me to get a good look at my dick at my new size. I watched in amazement as the head of my shaft wiggled with the rest of my cock, looking soft, gentle, less wide, and… adorable. Shockingly adorable. Like a delectable little mushroom.

The shape. The texture. The sensitivity. The size. It was all so familiar. My sister’s pussy, it did something to me. No longer did I have a masculine cock, firm and large and meaty. She had given me a smaller one. A feminine one. A pretty one. A cute one.

A girl’s one.

“I have a girlcock now,” I whispered. “Oh my God.”

“Goddess,” Calli corrected me. Her pussy plunged down on my girlcock again, swallowing it up whole. “Oh, it feels so good. So rigid, yet so gentle. So cute to play with.” My sister threw her head back and moaned. “Your girldick is perfection, little sis.”

Calli’s riding grew faster and harder. With every bounce, my breasts swelled under my sister’s hands, fuller, rounder, and more supple. More heavy. No more aching nipples, and no pointy budding shaft like the crossplay girls just starting hormones. Calli had left me instead with supple, soft, and rich growth, like I had been on prog for years.

I looked over my arms. My muscles had already disappeared, replaced with curvy fat. I licked my lips and felt the changes there too, my tongue tasting the gentle thin texture across my mouth. Even the musky odor of my sweat had faded away, replaced instead with an oddly sweet aroma that mingled pleasantly with the lavender smell that still permeated the room.

But best of all, I saw what happened to my belly and hips. My stomach stayed thin, but with an added layer of soft padding placed onto it, giving me a lower tummy pouch like a fertile Greek goddess. My thighs grew wider, plumper, with Calli’s own thrusts smacking against them, causing wet slaps and thick reverberations to resound across the room (and my skin). My sister, recognizing the changes were working, moaned even louder, lowering herself completely onto my shaft and taking in all of me.

Every single inch, enveloped by my sister, gone within her pussy. Then and there, she cried out as she felt my bush against her own, calling to me in my name. My new name. The one my own flesh and blood had chosen for me, almost certainly many months in advance.

“Kyria!” she cried with that wonderful name. “My beautiful Kyria. My precious, precious Kyria.” She drew her entire body forward, bringing her face close to me now, riding me as her burning pink hand caressed my soft new cheeks. I stared deeply into her bright eyes, looking at the blue irises within, falling deeper and deeper into her otherworldly vision—a sight I only could have dreamed of in our wildest roleplays. “My wonderful sister.”

“My lovely Calliope,” I whispered.

“Can I kiss you?”

My reply tumbled out of my mouth without a second thought. “Always.”

Hungry lips enveloped my own. I felt warmth surround my mouth as I realized the light burning from Calli’s womb and eyes was also coming from her own tongue and mouth. Faster and faster, my sister’s thrusts refused to yield as she rode my stiff girlcock. I only kissed her deeper in response, pressing as close to her body as I could, allowing her to draw me in so our breasts could press tightly against each other as we embraced our love.

Briefly, I broke away from our urgent kiss. My first kiss. “I think I’m going to,” I whimpered.

Calli pulled on my bottom lip. “Yes?”

“It’s going to happen.” Her warm lips remained parted, her tongue begging to touch mine.

“Then do it,” she moaned into my mouth. “Cum inside your big sister. Give her your seed.”

Calli shoved herself inside my mouth. Our tongues embraced, and Calli’s pussy swallowed me whole. I bucked my hips and cried out as her entire pussy squeezed on me, gripping me pleasurably, hungrily.

A sensation I had never experienced before came over me. Waves of pleasure, one after another, they shot across my body like a tide coming to shore. I felt its ripples coarse through me, making me shake, quiver, moan, cry. Primal wails filled the pink light of my sister’s mouth, and her arms held onto me for dear life as she consumed me, pounding onto my pelvis, taking me, taking me, taking me.

“Just like that,” she said, warmly, motherly. “Let your big sister soothe her baby girl.”

A wet, sticky seed seeped from my cock into my sister, flowing into her with throb after throb from my feminine dick. Its mess squirted out shyly into her cunt, pouring out of my head and down my shaft, enveloped hungrily by my sister’s pussy as she pushed it deeper into her womb. I felt Calli squeeze tightly onto me and cry out as my cum continued to seep into her, laughing in delight as I surrendered my life essence to her, my body still shaking, my new breasts surrounded by Calli’s own.

Orgasm after orgasm came, with my sweet, sticky, transparent cum leaking out of my head and into Calli. Slowly, my sister loosened her grip, pulling her pussy off my cock and holding a hand to her womb.

“It’s in there,” she said. “The ritual is complete.” The pink light from her eyes and mouth began to fade. Her breathing grew heavy and exhausted, her skin covered in sweat. “Oh. Oh fuck,” she gasped, her eyes rolling back in her head. It dawned on me that transforming a “boy” into a Shield may be far more taxing than I realized.

Calli’s moans and cries lessened, losing their serene edge, coming back down to the mortal plane. I watched her take a deep, long breath, her gaze wandering around the room, as if trying to ground herself back in mundane reality.

Slowly, she took me in, looking at my arms, my chest, my belly, my thighs. “Kyria,” she said, her face reddening, “you’re fucking curvy.”

“Am I?”

“It’s really hot.” A hand went for my tits, and she cupped them, groping them, sizing them up. I moaned, leaning into her touch. “You look like a little sexpot.”

“Oh God,” I whispered. “Erm, I mean, ‘Oh Goddess.’”

Calli laughed, panting still, sweat dripping down her hair. She drew loose strands out of her face and looked at me, a gentle, loving gaze in her eyes. “Do you want to see what you look like in full?”

“Yeah, I’d like that.”

She fumbled with a button next to the bed, and an overhead mirror sprung up from the ceiling. Slowly, Calli pulled back from my face and straddled my hips, arching her back to look up as well.

“See for yourself,” she said, lazily running a hand to her pussy, licking up the cum dripping from her lips.

I took a deep breath and gazed upon my new form. Round breasts, perky and fertile. Thick thighs and hips. Padded tummy, hinting a womb underneath, if not for my beautiful girldick. And then the short hair, thinner, shinier, prettier, like a futch lesbian’s cut. Not to mention how my skin looked. So smooth and gentle, with a round face full of extra padding around the cheeks.

And then there was my cock again, smaller, slimmer, dribbling cum like teardrops onto my pelvis.

“Wow,” I whispered. “That’s me?”

“And we finished the ritual successfully, so,” Calli said, sucking on her fingers, “it’s you forever.”

“I… my goodness.”

My sister giggled. “Glad you like the handiwork. Your voice is the one thing we’ll need to work on. But it won’t be hard.”

I looked up at the computer, where the terminals had closed themselves out, and the ecchi drawing of my sister and I remained. I looked at myself in the image, then back at the mirror, and then back again at the drawing. It was remarkable, really, how realistically the artist predicted my female form.

“So, um,” Calli said, letting go of my collar. “How was your birthday?”

I smiled warmly at my sister, the love of my life. “This was, without a doubt, my favorite birthday gift ever.”

Calli dove onto me, let out a squeal, and kissed me again. And as I felt her body fall deeper into mine, our lips intertwining once more, I reminded myself to ask her what time to wake up tomorrow for my first day as a Magical Girl. As a Majestic Shield.