Sissy for Sister

Author's Note: This is a fictional story about a brother and sister relationship featuring gentle female domination over a crossdressing brother with gay sex and chastity. Since each chapter may contain content that falls under different categories, please refer to the 'Story Tags' tab under 'Story Info' for a list of categories this chapter includes.

This is the final chapter of this story. Thank you to everyone who stuck with the story to the end. Though my storyboard was planned out in advance and I couldn't change the story to incorporate feedback without potentially major delays, I do appreciate the feedback I received and will try to incorporate this feedback into future stories.

Again, to all the people who followed my account, favourited my stories, left comments or just read them, thank you from the bottom of my heart.

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Myles had been baking gingerbread for his sister. She allowed him to wear an apron for protection but nothing else besides oven gloves. Sienna arranged the presents under the tree in her Christmas pyjamas one last time, on Christmas Eve. Hiding her devilish smirk, she stood and held one present up.

"Sissy toy, what is this? You got me this present, but it has different wrapping paper to the others. How am I supposed to arrange the tree like this?"

"I'm sorry, Miss Sienna."

To her signal, Myles put down the tray, took off his apron and knelt in front of her. She pressed at his chastity cage with her barefoot, and played with his balls. They didn't quite feel full yet, but looked so sexy all the same.

"Have anything to say for yourself before I decide your punishment?"

"N-No, Miss Sienna."

"You don't sound too certain."

"I didn't... I mean that I don't... I don't remember wrapping a present in different wrapping paper. I'm sorry."

Then, Sienna giggled.

"I wrapped it. I'm just kidding, you're not getting punished. Stand up."

When he did, she handed him the present. On the label, it was addressed from him to her, and was definitely in Sienna's handwriting. She wore her sweetest look, eagerly awaiting him to hand her it back.

"Well, it is unsightly next to my other presents, don't you think? Should I open it now?"

"Y-Yes?"

"I think so too. See, I got this for myself because I knew you would be too shy to buy me something like this, even though you are my boyfriend."

Sienna carefully unwrapped the present, and revealed a skimpy lace bodysuit cut like a one-piece swimsuit. Through the material, one would be able to see her entire, sexy body.

"I love it. Thank you, Myles." Sienna kissed him on the cheek and took a few steps back. "I bet you're dying to see me in this. I'll just be a moment."

Myles didn't take move a muscle. He wanted to see her wearing it. He couldn't wait. He worried there would be some trick, that this present wasn't for him, really, but would be for other men to enjoy. But he waited with bated breath regardless.

The trick was obvious when Sienna returned from the bathroom. Though he could see the shape of her breasts pushed up by the fabric, her toned stomach and her wide hips, her nipples were hidden by pasties under the bodysuit, and string panties covering her pussy.

"Tada." She giggled. "Looks like my spell worked on you."

"You look so beautiful. I am so glad I get to be your brother."

"You're sweet. But keep some blood circulating your body, yeah? I've got another surprise for you. Since you got me this early present, I was thinking I could give you one. How about I let you see more?"

"You mean...?"

"I'll take off the pasties and the panties and even the bodysuit if you want me to."

"Yes, please, Miss Sienna. I want that."

"It's not that simple. I'm content to let you go your entire life without seeing me naked. I'd find that really hot. I get so wet denying you and torturing you like that. But I'm not just your Mistress, I'm your sweet little girlfriend too. So, I've decided how I want to do this. Remember how you can kiss me for extra denial time? I've decided to offer you glorious sight of my body for one extra month denial time."

"One whole month?" Myles whimpered. Sienna nodded confidently.

"Don't try flashing those puppy dog eyes at me. It's not going to work. I'm not making you do anything. You accept, and you can dress me up or down in whatever way you want for a whole hour. For one month and one week, you can get me nude and kiss me. And since I've decided to let you cum tonight for being such a good little sissy, you can even lick my pussy and fuck me with a strap-on."

The offer was too good to pass up, Myles tried to put his lips to Sienna's but she pressed her fingers up against his mouth and held him back. She wanted him to say it. To accept that if he took the deal, he would not get to cum until February at the earliest. But since Sienna would wait until she thought he had earned his orgasm and then count down the extra days of denial, it could be longer by days or weeks. He shuddered to think that it could be an extra month or more.

"Miss Sienna, are you sure you want to offer me this? If I see you naked, you'll have lost your chance to deny me that pleasure for the rest of my life. You said denying me makes you wet."

"I know. I like to tease you. But you make me wet as well, and having you look at my naked body, I bet your face will be all the pleasure I can handle."

Myles felt his cock harden and struggle in its cage, accompanied by dribbles of pre-cum from it down onto the carpet below.

"Okay. I want to kiss you and see you naked and get to have sex with you."

Sienna smirked. Giggled and stepped away.

"Good boy. But I'm just a silly little girl. Could you check my maths for me? One month, plus one week, is how long?"

"One month and one week. That's how long you'll have to deny me on top of my ordinary denial period."

"Mmm..." Sienna hummed happily while she touched her crotch. "Knowing what it's going to cost you makes me wetter than denying you, even for a lifetime. And I'll get this wet every time you get to see me naked."

Sienna headed for the bathroom again, and looked over her shoulder at her brother.

"Close your eyes, and don't open them until I tell you to."

After Sienna returned from the bathroom, she ignored Myles and headed upstairs. It only lasted a moment, and when she returned she stepped up to him, and whispered softly.

"You can open your eyes now."

A brief moment of hesitation held him back. A pang of sadness. That he'd never get to relive this moment that the girl he loved so much showed him her naked body for the first time. But he opened his eyes and felt his heart shatter. She was dressed in her pyjamas again and wore her strap-on.

He didn't dare say anything until she broke into a fit of giggles.

"Okay, okay. Here, you'll need this." She took off the strap-on and handed it to him. And then took off her pyjama top to reveal the bodysuit underneath. Now, the pasties were gone, and he got to see her perfect nipples for the first time. Such cute pearls in front of small areolas. She was incredibly perky, threatening to tear through her bodysuit.

She pulled down her trousers to show him her pussy. She had a little patch of hair adorning her pelvis. She kept her labia completely bald. Her fat pussy lips hid much of her labia minora, and she hadn't lied. She was dripping wet.

Even Sienna seemed nervous to be crossing this boundary with her own flesh and blood. She cosied up to her brother and adjusted her glasses. She let down her twin buns, and pushed all that hair back over her shoulders. Still, Myles just stood frozen.

"Don't just stand there like a wet flannel. You're paying for this, Myles. You only get an hour, remember?"

"I-I..." He didn't seem to be able to respond, so Sienna took his hands and placed them on her breasts.

"Your hands are so lovely and warm."

Feeling his heart rate skyrocket, Myles could barely focus on the feel of his sister's firm, yet soft and tender breasts. Not very large, but perfectly shaped and incredibly arousing.

"So what do you think, should I keep the bodysuit on, or take it off?"

"Keep it on. I love it."

Myles pulled her over to the settee to do what he'd wanted to do to her from the first day she took his keys and declared herself his Mistress.

He parted her legs, and kissed at her cleft of Venus. He pulled the crotch of the bodysuit to the side, and Sienna put her head in her hand, resting her elbow on the arm of the settee.

"So cute and eager. Go on, but you're not allowed to cum until I tell you." As if to make sure he wasn't going to cheat, Sienna slide one foot underneath him and toyed with his cage while he pressed his tongue against her and licked. He moaned when he tasted her incredible nectar. He'd never licked a girl before, never smelled her pussy. He'd seen one naked in person, getting fucked by one boy while he got fucked by another. They'd even kissed, but he had never done this. He didn't know how, and his sister wasn't offering too many chances to practise. He wish he had bought a masturbator to practise on. He vowed to, after this, in case Sienna ever gave him the change again. If she found it, he knew she'd laugh until her sides split, but he wanted to be good for her if she ever let him do it again.

He licked up her length a few times like a dog licking its feet. And Sienna realised.

"You haven't ever done this before, have you? That's okay, I won't make fun of you. Just, use your hands to part my pussy and get your tongue inside. And give my clitoris some love, too."

Following her advice, Myles pushed his tongue deep inside her. And she felt so warm and soft and delicate. Locking eyes with her and seeing her squirm and writhe, and knowing finally that he was the one making her do it, feeling kinship with the men who had fucked her, he thought about all their cocks that had barraged this tunnel before his little tongue, and licked more forcefully as if to find some leftover cum or taste their cocks in her. Sienna closed her eyes and laid back.

"This is wonderful. You're such a good boy."

Myles moaned a response, and kept exploring her insides. The warmth. The wetness. The smell. And the thought of the other men who had been intimate with her pussy. All those lewd aspects of this swirled in his head into a cacophony of sexy thoughts that threatened to send him over the edge. His orgasm was still distant, but a little pre-cum oozed out onto Sienna's foot. And it caught her attention immediately.

"Remember what I said. Not yet."

Now, Myles pulled his tongue from her and lapped at her clitoris. He flicked it with his tongue, he ran circles around it. He sucked it. And after all that, he kissed it. Seeing Sienna so content to let him continue, he licked her again. He varied his movements. And teased her with his hands, and massaged her clit when he wasn't on it with his tongue. And after ten minutes, Sienna came on his face. Her nipples seemed even harder now, and pressed her body violently into the settee. Her hips bucked and raised and Myles grabbed her by the waist and pulled her forwards, only realising after that he was grabbing her firm arse. Feeling her orgasm, suddenly he felt his own approaching. He wanted to move this along.

So Myles stood up, and put the strap-on on. He hadn't needed to wear it, but enjoyed taking a hold of it once it was in place, like it was his own. His wasn't so long or thick, or rubbery, with working foreskin, but having been caged for just under a month, he was quickly forgetting what this felt like. Sienna giggled again at his expense.

"You are an open book, sissy toy. Do you hate that I'll never, ever let you have another erection? I have a multitude of ways to make you cum, I just don't see the need to ever let you out of your cage when spilling your sissy seed is your reward. Honestly, I spoil you enough as it is."

"N-No. I love being caged all the time, Miss Sienna. It's just... Different. From how it used to be."

Sienna leaned forwards and put her lips around the dildo. Seeing her sucking cock from this perspective almost broke Myles. She didn't go for long, knowing it was his precious time she was wasting. Just enough to get his little cock dripping.

"Mmm... So tasty. I want it inside me now. Come on, fuck your little sister. You've never done this either, have you? Would you prefer I lead? Would you like me on top?"

"Y-Yes please. I don't want to go too fast or too hard. I don't want to hurt you."

"You're so silly. I use that dildo all the time. I know every little bump and groove and my pussy is perfectly moulded to its shape. Fuck, I'm actually in love with that dildo. I want to be its cute little waifu. But I love being on top too. And with a sissy, it wouldn't feel right to be on the bottom."

Myles sat down, and Sienna parted her legs, straddling him. He traced her curves. Her legs were so firm and slender. More than anything, he loved finally getting to be intimate with her, it wasn't even about watching her orgasm, tasting her pussy or seeing her bare boobs. It was getting to enjoy moments like this.

Sienna pulled aside her bodysuit, and speared herself onto the dildo. Her expression melted away to one of bliss. In just a few thrusts, Myles really could tell that Sienna loved this cock. Imagining the sort of face she would make if she had to ride his cock made him leak and leak.

He hissed through his gritted teeth, and Sienna forced herself to glance at him.

"Are you about to cum?"

"Yes, Miss Sienna. I don't think I can hold it."

"You'll have to." She answered. And she sped up on the dildo. "Hold it until I cum. Let's cum together."

She bit her lip and looked into his eyes sweetly. Sweat dripped down her face and her glasses slid down, almost about to drop off her face. Her hips swayed like waves in the ocean, rising and lowering her pussy on that cock, going all the way up to its tip and all the way back down to its base in a smooth motion. She rested her hands on Myles' shoulders, and her breathing increased. As she scrunched her eyes and tossed her head down to the side, she came. And Myles, watching her cum a second time, fired his load from his little cock.

Sienna collapsed against Myles, and he grabbed her by the butt, propped her up and kept thrusting into her. She cooed and kissed his neck and his cheek. And then his lips. They kissed and kissed and let their tongues lash against each other, and soon enough Myles tossed Sienna off of him. She fell down to the settee on her back and giggled as Myles mounted her. He thrust the dildo into her but his expression was one of worry at her reaction.

"Keep going. I just thought it was cute, that's all." She encouraged. Myles nodded and fucked her with that big dildo. Sienna leaned up and wrapped her hands around her sissy boyfriend. He wrapped his arms around her too and they kissed again, as he pumped in and out of her. Her pussy squelched with each thrust. He felt her tense as she was about to cum again. And she felt the same.

"Are you...?" She didn't get to finish. Her orgasm cut her off.

"Yes. I can't hold it..." Myles groaned.

"Do it!" She cried out. Myles came again, and the two collapsed onto the settee. The dildo remained inside Sienna, and she squirmed a little to get more comfortable. A long smile drew across her face. This felt perfect. Her brother wasn't too heavy, and his sharp breaths against her neck made her feel so sensitive and perfect.

Myles' hands explored Sienna's body for the rest of the hour, but they didn't move from that spot on the settee, until Sienna's phone beeped to warn them that his time was up. Reluctantly, they both began to move, and Sienna stood up. She pulled her bodysuit over her wet pussy, and headed to shut off the phone.

"I hate making these sorts of promises. I always feel so mean following through, but you need to help me do it. If I let you cum before your extra denial time is over, you need to beg for a really severe punishment, understand?"

"Yes, Miss Sienna."

His sister collected her pyjamas and put them on over her bodysuit, hiding away that perfect body from his hungry gaze. Myles didn't know when he might next get to see her naked, if ever, and that excited him to no end.

"I'm serious." Sienna muttered. "Do you know how much I just wanted to lie there with you forever?"

"You'll get there eventually." Myles tried to comfort her. He took off the dildo and placed it down.

"Thank you, Myles. You give me strength. We were made for each other. I don't care that I'm your little sister. That only means there was no chance we might pass each other on the street and never meet at all. I am so glad that I get to be your girlfriend. That out of everyone, you chose me."

Flashing that cute smile again, Sienna ran up and offered Myles one last kiss. But it was his turn to smirk. He pushed her back gently, and she looked gobsmacked.

"Wh--?"

"My hour expired. If I kissed you now, who knows what sort of punishment I'd have to endure."

Sienna giggled, and, filled with energy and passion, she skipped over to the kitchen area.

"Good catch, sissy toy. I'll just have to give you a peck on the cheek instead. But that can come later. We need to get the turkey and veggies ready for tomorrow. Come on, little slave, you can be my sous-chef."

"Y-Yes, Miss Sienna."

"That's Miss Chef to you, sissy toy!" She giggled. Myles rushed over, and they got to work to follow their perfect Christmas Eve up with a perfect Christmas Day.

Christmas Day began with Sienna pulling Myles out of bed and leading him downstairs to rip apart their presents. She really had turned back into that bright-eyed little girl, and looked so sweet and innocent on her knees beside their big Christmas tree. Christmas classics blared over the TV, and Sienna loved the gifts Myles got her, while he noticed a theme among the slutty clothes, sex toys and bondage restraints she got him.

They prepared dinner. And while it cooked, they had a little more fun. Sienna had Myles put on some of the girly clothing he had received from her, but not his wig or makeup. And there, on the settee, she sat wearing her big strap-on, a mirror image of the night before, as this time Myles bounced up and down on that cock, as it carved its way into him, to make him fall in love with it as it had Sienna. As it made his arse never forget its delightful shape.

He bounced and he bounced to the instruction not to cum. He moaned like a slut and Sienna smirked devilishly. She giggled at his expense to no end. This was the perfect day, she felt. Nothing could top this, and certainly nothing could ruin it.

But her heart stopped when she heard the door handle crank. And the door creek open. Myles froze still, as Sienna did. There was no time to do anything. And a woman's voice called out.

"Merry Christmas kids! I'm home!"

"M-Mum...?" Sienna squeaked.