She feminizes you...

Crystal returns with a huge bag and thumps it down in front of you.
"I've picked some outfits that you will try on,"

You look down in dismay at the bag of clothes.
"Go on, open it. Your first outfit is on top," she instructs,
You tentatively unzip the bag and immediately spot pink. This can't be good.
"My last boyfriend loved these outfits, but when he left, he left them behind, so now we can put them to use!"

You open the bag. The top outfit: Long, white thigh-high socks, a pink accordion skirt, a white blouse with a pink collar and stripes on the sleeve and a big pink bow on the neck. Below that, a pair of pink, lace panties, a matching bra and a black, nylon tube which you weren't entirely sure what it was.

"A waist trainer. Like a corset." She smirked, "Now strip, and put them on or I will **** them on you."
"Mistress," you begin, trying to appeal to her, "I really do not want to,"
"Do I care? I own you. Now dress up sissy!"

Your heart is thudding wildly as you begin to strip down. First your pants, then your underwear.
"Is that all you've got?" she giggled, pointed at my dick, "Also, you are so hairless! I was going to shave you but I don't need to!"
I ignored her and hesitantly lifted the lace panties. She was staring at me intimidatingly, tapping her phone as if to say 'Dress now, or the world finds out'.
I stood, raising the the lace panties up my already-smooth legs. They barely covered my manhood and they rode up my ass. Crystal was giggling madly and snapped a few photos. I lifted the bra and slotted my hands through the supports. I struggled to hook the bra at the back but eventually managed. The bra was clearly fitted for someone broader than Crystal. I only noticed once it was on that there were false inserts in the bra - about a C cup.
"Now the waist trainer, just slip it onto your stomach," she explained.

I lifted the nylon tube and pulled it up and around my waist. She circled me and tightened it.
"Mistress, it's so tight!" I wheezed,
"It's meant to be. It sucks in that waist and makes it far more suitable. Now keep going."

Struggling against the tightness in my waist, I lifted the blouse and slid it over my head. It too was tight and was straining against the false breasts. The sleeves ran halfway down my bicep. the pink bow and trim was especially feminine and humiliating. Next I raised the skirt and wrapped it around my hips. Crystal ensured the shirt was tucked into my skirt. Finally, the socks ran all the way up to my thighs. Admittedly, the outfit felt nice, but I hated what it did to me.

The camera clicked, capturing my new outfit and my face clearly in view.
"Lift your skirt, show me your panties, sissy!" she laughed.
She already had photos of me in this outfit, I sure as hell didn't want that going out in the wild. I lifted my skirt and revealed my slightly bulging panties. Another photo. And another, of me exposing my pantied butt. Crystal showed me the images, apart from my face, I looked like a woman. The cinched waist gave the illusion of wide hips and bigger breasts.
"Finally, put this on!" she tossed me a long, pink wig. I affixed it over my short hair. She instructed me to pout, and pull the infamous duck face. Then, more photos with me kissing her butt, or as her footrest - but dressed in this pink, feminine outfit.

"Mistress, you said these were for you, but they are easily too big for you?"
"No ****, I said my boyfriend loved them. At least he did after I **** him to wear them. I have so many outfits of his left behind!"
"What happened to him?" I asked, terrified of the answer,
"I left him, somehow he managed to cheat on me. Last I heard, he was a fairly successful e-girl on twitch now. I still have the only keys to his chastity belt," she smirked.

"Anywho," she digressed, "Now that I have all these photos of you, I just want to say, I have no intention of deleting them. I will hold these against you forever. So unless you want the world to see that you are my sissy, ass kissing bitch. You'd better submit to me forever."