The Changing Dynamic

Dan: Are you sure you'll have time to reply in between beating all the men off?

Steph: Have I ever told you that you're a charmer?

Dan put his phone down, elated with the jump from the dating app to messaging directly along with the acknowledgement that came with it. It felt like this invisible wall separating fantasy from potential reality had cracked. He got himself ready for class without time for another orgasm, wondering how he'd ever concentrate on the 3 hour lecture. Louise was waiting for him at the door as they shared a class, with her studying Criminology. An hour in, he got a telling vibration from his phone.

Steph: Okay, you clearly have good taste as I've had a lot of second glances on the train today and one of the married men here is definitely being more flirtatious than he should be.

Dan: Well, it is a very complimentary shirt....

Steph: Thought you weren't a boob man?

Dan: Are you complaining?

Steph: No, just trying to keep my nipples under control now they know you're impressed with them!

Dan: I don't want to say it's all your fault but you should have picked more padded bras as the options.

Steph: I wanted you as horny as possible in class, so as long as that's the case, it will have been worth it.

Dan made sure Louise couldn't see his phone and carried on messaging. He'd have to ask for her notes after class and briefly wondered what she'd make him buy her as a bribe.

Dan: I'm VERY horny. I shouldn't have left my room without doing something about it.

Steph: If I was there I'd have done it for you.

Dan's eyes widened. They'd said a lot to eachother and shared way more about their tastes and desires than siblings should but this was the first time either of them had explicitly said they'd act on it to the other. Steph followed it up quickly.

Steph: I shouldn't have said that.

Dan: No you shouldn't....

Steph: Sorry.

Dan:..... because now I'm harder than ever and imagining that red lipstick sliding up and down my dick.

Steph: And kissing your balls... and further down if you wanted me to go there.

Dan felt goosebumps on his skin as he read the message.

Dan: You'd do that?

He waited a few minutes and didn't receive a response. No doubt she was busy with work and would reply when she could. It was after the break in the middle of his lecture that she did respond. He'd grown softer but was immediately hard again, thinking about the possibilities.

Steph: I don't think there's much I'd rule out for you...

Steph: I can't believe the way things have escalated. You're my little brother but I feel like a switch has been flicked and now I can only see you *that* way. What have you done to me?!

Dan: Genuinely, I have no idea. I feel the same. Ever since we went for a drink, it just felt like a date in hindsight and now I can't stop thinking about you as though it was.

Steph: That makes a lot of sense, when I got home after our drinks I thought about doing things with you. I expected to wake up feeling horrified but I didn't. I trust you, I'm attracted to you and I think we could have the dynamic I've been looking for.

Dan read the message, heart pounding.

Dan: Agreed but perhaps we should talk about it in person. Wednesday at lunch?

The reply came quickly.

Steph: Sooner, tomorrow evening?

Dan quickly cancelled his plans.

Dan: Sure, I'll have a think and let you know where. Don't forget how I want your hair.

Steph: I won't, Sir. By the way, you can't imagine the state of my underwear right now. Even just calling you that has me soaking for you.. Grey was a smart choice.

Dan: I'd tell you to show me but I'm in class and an image is hard to hide.

Steph: Lucky for me then as the embarrassment would probably kill me.

Dan: We'll have to work on that, I can't have you being shy about all the things I want to do to you.

Dan smirked, he knew his sister well enough to know the curiosity would be killing her.

Steph: In that case, maybe we should play a little game later, titled 'You share your fantasies and I'll try not to cum'.

Dan shut off his phone for the discussion part of the lecture and wasn't surprised to discover he was completely at sea with the topic. Louise sighed after class and asked for an upmarket supermarket steak and chips for dinner in exchange for her notes.

Dan went back to his room after a detour to the supermarket, unpacked his bag and turned his phone back on. Steph had left a few messages before realising he had clearly turned his phone off. He messaged her back letting her know he was back in his room and about to go for a run. Steph apologised and said she was now going to be busy for the rest of the afternoon and would speak to him later.

He had no complaints with that, he needed a run to clear his head and prepare for Steph's little game later. After a thoroughly exhausting run which came close to his personal best followed by a healthy early dinner, Dan read through Louise's notes and caught up with the class he might as well have missed. Soon after his phone pinged. It was Louise thanking him for the steak. He was disappointed it wasn't Steph and decided to message her again.

Dan: Up to much?

Steph: I've just been working out. I need to keep my body in good condition should I ever find the right man to enjoy it.

Dan: Makes sense, a flirt like you with a face like yours needs a body that can handle a pounding.

Steph: Anyone seeking to give me a pounding should be very grateful to my gym trainer and my pilates coach, now I think about it.

Dan: I'll be sure to send them flowers.

Dan laughed at his little joke and told her to message him when she got back in. Yet again he marvelled at the change in their dynamic over the last week or so, it was incredible. It felt like a question of when, not if, they'd take the next step. He remembered he needed to find a good place for tomorrow and set about finding one. He decided on a different bar, fancier, playing light music in the background. It wouldn't be cheap but Steph, sister or not, was worth it. It was at a great location between her work and house. He didn't want to presume but also didn't want to pretend it wasn't a possibility.

After Steph had got back and made dinner, exchanging a few casual messages with Dan, she asked about tomorrow evening and mentioned she was due to work from home that day.

Dan: I've booked a place, it's about the same distance from your house as it is from your work, so you should be fine.

Dan implied it was deliberately chosen due to her unknown work arrangements though they both knew what he'd done and why.

Steph: Great, what do you want me to wear?

Dan: Something dressy.

Steph: No Dan, what do you want me to wear?

Comprehension dawning for Dan, he thought for a spell. This could be interesting he thought.

Dan: Okay, I want you to wear a tight fitting but classy dress, preferably red, black heels that are not too high and underwear that I'll pick from 4 options that you find appropriate based on what I want you to wear. You already know how I want your hair." He'd need to start educating himself on her wardrobe and general fashion if this was going to become a recurring theme.

Steph: Wow, okay, that is.. wow. Yes Sir.

Dan smiled at her response. He was starting to really understand her tastes and desires. He wanted to learn more and made a mental note to ensure he focused and probed on it tonight and during their date tomorrow.

Half an hour later, Steph had sent a picture of 4 sets of underwear. Two red, one black and one dark blue, which he recognised from earlier in the day. He was instantly drawn to the black set, it looked sexy, all lace and thrill. That the set included a thong added to it.

Dan: Black set, definitely.

He could see her feet unintentionally in the picture and struck by a thought.

Dan:....and I want your nails to match the set.

Steph replied in the affirmative and went off to prepare. He took the time to iron a shirt and shine his shoes. Steph messaged him a short time later.

Steph: Fuck me Dan, it is so hot when you're demanding like that. Just getting myself ready for tomorrow, knowing everything I was doing was to please you when you see me, I could barely cope with my horniness.

The message spun off a wealth of possibilities for Dan as he imagined being able to unrestrain himself when it came to wanting things. Deep down he was a perfectionist and a thinker. He didn't expect to find someone who would want to see that much of that side of him. Steph seemed to want to. He resolved to explore that a little more with her too.

Dan: You like pleasing a demanding man.

Steph: Yes, sometimes the more demanding and the harder it is, the more I want to do it. In the right situations, obviously. Sometimes my exes have completely overshot their place and started demanding stupid things like wanting to have access to my phone all the time or whatever. That's lack of trust, not a show of dominance.

Dan nodded, he got that.

Dan: I wouldn't be that foolish. Be stupid to ask such things when I know I'm demanding enough to keep you too busy for anyone else.

Steph: There you go again, ruining my underwear Dan... want to make it worse?

Dan: Always...

Steph: Tell me some of your fantasies.

Dan: Only if you share some of yours.

Steph: Okay, 2 of yours gets you 1 of mine, deal?

Dan: Deal. I've been thinking about the football story and getting head while Arsenal were playing. And public stuff.

Steph: You're such a guy, but yes I can see why getting head while your team plays would be a fun afternoon... if they win! What kind of public stuff? I won't share mine until you're clearer.

Dan: Sex in a public place.

Steph: Hot. A remote control vibe, also in public."

Dan: Just as hot. 1) having all 3 holes in one session. 2) getting head while actually being watched.

Steph: You weren't kidding about me needing to be less embarrassed! Though I must admit I've had the occasional fantasy of being shared.

Dan nearly choked.

Dan: You'd really want to be shared?

Steph: Yep, if I trusted him and whoever he was sharing me with. Being seen as a possession to be shared would be thrilling.

Dan: You are something else Steph!

Steph: I know the normal thought process about something like this is that I must have something seriously wrong with me or some unresolved Daddy issues, but I don't. You know me, have I ever been anything less than 100% about something when I commit to it? I know what I want and what I like. You're seeing a bit more of a... wild side to me than most men because I trust you. Besides, you can keep me to yourself if you want....

Dan: Maybe at first, until I've stopped having constant hard-ons whenever you message me."

Steph: Tomorrow....

Dan: Seriously?

Steph: Yes, if you want to.

Dan: You know I do. I'm going to cum thinking about it right now.

Dan pulled his shorts down further and wrapped a hand around his sizeable penis.

Steph: I want to cum...

Steph left it hanging there, waiting for Dan's response. He knew what she was angling for.

Dan: You're not getting my permission gorgeous, until you've swallowed my cum.

Steph: Fuck, stopping myself crawling under the table tomorrow is going to be torture.

Dan read it and shot a load over his chest, deliberately not using any tissues. So far they hadn't seen eachother naked and Dan was going to keep it that way, for the most part. He snapped a picture of his cum-covered chest, avoiding getting his softening penis in shot and sent it to Steph with the caption 'are you sure you can swallow all of this?'

Steph: I just moaned. I'm a cum addict, are you sure you can make enough to keep up? Night Champ...

***

Steph had got to the bar first this time, to Dan's annoyance. Train delays on the unreliable London tube had left him about 10 minutes late. When he got there he saw Steph sipping a cocktail. She looked confident but he knew his sister enough to notice the slight shake to her hand as she held her drink. She was nervous.

"You look incredible!" He said, as he walked up to her.

They moved closer and Dan took the lead, kissing her cheek and taking her hand so he could look at her more closely. The dress was indeed red, plunging down to her chest, showing off ample cleavage as it wrapped tightly around her and crossing behind her back, showing plenty of tanned skin as it finished mid-thigh. Her hair was as he expected it to be, as was her nails. Her shoes were black and strapped, matching her nail varnish. As Dan looked back up he could see a slight rise of material at her breast area. Her nipples had risen at his appraisal of her and the thin bra he had chosen for her did little to hide it.

"Incredible" he said again. He saw and felt Steph relax a little more. "You were nervous about my approval, weren't you?"

Steph nodded instead of answering and Dan again recognised how the dynamic had changed. It felt as though Steph was already submitting to him and that gave him a boost of confidence to take the initiative and give her some reassurance. He took her hand in his and kissed it, looking her in the eyes, he saw the colour rise in her cheeks.

"You're stunning Steph, you have nothing to be nervous about." She smiled and Dan ordered a drink with the passing barman.

They settled into what could be considered a standard early date. General conversation about their day, laughing at awkward first dates, crazy University experiences and friends as well as Dan's plans for his birthday at the end of the month. It felt good, all the way through. Steph was excellent company and Dan couldn't understand how she was still single, despite her specific tastes. She was 25 but excelling in her career at a trajectory far above standard for her age, had managed to buy her own house (with their parents help) and was clearly keen to settle down. Dan considered his own future as he approached 20 and despite the age gap (and ignoring the very obvious sibling issue), he knew he could give her what she wanted. Like the previous week, they'd had a fair few drinks though this time it was accompanied by dinner and as such, they both felt more sober though with enough of a buzz that they'd lost some inhibitions.

Steph demonstrated their shared lowering of inhibitions first, asking if Dan needed proof she'd followed his clothing instructions down to the garment. He nodded and then smiled as she rose and excused herself to the bathroom. Dan watched her go, aware of the sly and not-so-sly stares as she walked across the bar. He kept reminding himself how lucky he was and how improbable it all was too. She returned a short time later with her clutch bag close in hand. When she arrived at the table she paused a beat for nearby heads to get back to their conversations before showing Dan her bag. The thong sat inside, visibly wet.

"I couldn't handle the underwear lines, they were spoiling the dress." She winked at him as she said it. "You didn't get everything right today though," she smirked as she said it "you didn't check if the toilets were a good place for a sneaky blowjob. I checked, they're not. So we'll have to leave soon so I can suck your dick at home." Dan called the waiter over soon after.

The Uber arrived promptly and they got into the back seat, Dan holding the door open for Steph and then moving around the car to get in the other side. They moved in close to eachother and found themselves holding hands, a nervous energy rising in the back of the taxi. Dan, in part to calm his shaking hand, started to run his free hand slowly up and down Steph's thigh. She exhaled slowly, clearly aroused by his gentle touch. She took their joined hands and move it onto Dan's lap so that her hand was pressing directly onto his crotch. She ran her hand along it slowly, trying not to be too obvious. When she felt the full length of his penis and gave it a light squeeze for good measure, her eyes widened as she looked at him. She leaned in closer and whisper in his hear before nipping it "I can't wait to have this inside me. I need it."

***

The taxi arrived at Steph's house shortly after, both grateful for Dan's logistical skills. He'd only visited once, when Steph had initially moved in. It was a new build in a secure complex. They were careful and quiet going up the stairs to her 2^nd floor apartment, Steph taking some time to get the key out and into the hole, quipping about this mirroring Dan's potential performance as she did so. She let Dan through first and then followed, locking the door behind her. As she turned around she came face to face with Dan, only inches away and given her heels, at almost the same height. They looked into eachother's eyes for a moment before Dan leaned in to kiss her. Steph returned the kiss with passion and was soon pushed against the nearby wall as they kissed frantically. Dan's hands were all over her, feeling her body, running a hand up her legs, over her shapely ass and up to her breasts. Steph was alternating moans with deep exhalations and the occasional 'fuck' as she rubbed his thick cock back with vigour.

He took her hand and led her to the main room, it was as though she was a guest in her own house. It was his environment now and she was here to make it pleasurable for him. The thought aroused her and she leaked yet more of her juices down her thighs. Taking my underwear off was hot but impractical, she thought. She sat him down and promised to return after freshening up. She was gone for a few minutes and had unzipped her dress and taken off her bra, her hair had come loose from their kissing so she pulled it tight to her head and into a ponytail. She walked back into the living room, heels clicking loudly on the wooden floor, to find Dan had made them a vodka & lemonade each. She took a sip, grateful for the liquid and the courage. She bent to unstrap her shoes when Dan stopped her. "Keep them on." He'd not yet passed comment on her naked body and as she turned to him, she saw he'd taken his jacket off and was resting an arm over the sofa.

She took a step towards him but he wordlessly put out a hand making her stop in her tracks. He looked her naked body over. Her full breasts perked high on her chest. Pointed pink nipples around small aerolas. Flat, toned stomach seen in the picture but now looking perfectly proportioned for her chest. Wide hips hiding her firm ass. He saw her look at her pussy. She knew she had slightly bigger lips than most people. Her exes had liked it, would he? She'd shaved for him but silently cursed herself for not checking first. Would he take note? She knew he was inexperienced but she felt he would be filing it away to punish her later. God, they hadn't even talked about punishments yet.