Yes

Alex took a moment to think. His arousal was instant and obvious, her offer making his member stir. A dozen memories rushed to the forefront of his mind, of all the time they had spent together growing up, and how she had always been ahead of him, older, more mature, so very confident. It was true that he loved Clara, but he had also had the biggest crush on Lilly for the longest time. It wasn't as strong as what he felt for his girlfriend, but it was potent in its own way, and he could feel it rearing up in him now. His blood pulsed through his body, faster and faster, his mouth felt dry, and his cock began to grow stiff.

He worried for a moment, even as he tried to figure out what he was going to do next. Was it a betrayal of Clara? He didn't think so, their relationship wasn't exactly normal, and if he had chosen to fuck Lilly in the pool, she would have enjoyed it. But sleeping with her like this wasn't the same, was it? Back then, it had been part of their game, but their game was over now. Did that make it cheating? On the other hand, if he asked her, he already knew what she would say. He was the master, and it wasn't down to any lowly slave to tell him what he could and couldn't do. Then, she'd probably do something or say something to make him punish her, so she could get off while watching the two of them.

That decided it. Clara wouldn't mind. He would make it up to her later, confess and tell her what had happened.

"All right." He said. "I suppose that would be fine, slave. You're right, you're still my property for a few more hours. Whoever said that you could dress like a person? I should punish you for that. Take off your clothes right now."

Lilly shivered, a look of desire coming into her eyes.

"Yes, master." She purred, confident and seductive. "I'm so sorry, master. Please, let me make it up to you."

She took a handful of her pale top, and reached upwards, drawing it over her shoulders slowly. Alex watched, her bare skin was exposed by inches. Some part of him noted that only hours ago, he'd seen her completely naked. This wasn't new, and it wasn't surprising. So why did it have so much gravity?

Confidence. That was the answer. Lilly didn't treat it as something he'd seen before. Slowly, sensuously, she exposed herself, drawing the fabric up and over her chest, revealing her stiff nipples, and her naked top. With a flick, she sent the shirt flying, not even paying attention to where it went. Alex felt a straining in his pants, his cock growing harder as Lilly's hands flowed to her chest, cupping her breasts and squeezing them gently, running her fingers over her naked flesh with a smooth flourish, she was showing off! She didn't need to be told she was sexy, she knew it. In a way that Clara couldn't quite equal, Lilly had mastered her sexuality. She was putting on a show, but Alex realised she was very far from making herself an object. She had power, she had command. Even though she was the one stripping, even though he was the one called master, the power dynamic had shifted totally.

All through body language and simple confidence.

Lilly spun around, her hands working at the zip of her jeans, he heard it rattle for a moment, and then was pulled down. Rhythmically, Lilly started to pull the lip of the jeans down over her waist, revealing her naked skin. She was wearing no panties, as he already knew. She wiggled, pushing the jeans down, and then swung back towards him as she kicked them off, showing off her long, well toned legs. Alex felt his heart beating fast. The sight of her body transfixed him, her womanhood was already aroused, her slit leaking slightly, the same liquid beading her inner thighs.

Lilly's g hands went to her chest again, kneading the flesh of her bust, and playing with her nipples, catching them between her thumb and forefinger, and gently stimulating them. She threw her head back, and loosed a low moan that made Alex's spine shiver with want.

Alex's hands fumbled as he went to the wait of his own trousers, pulling them down with far less grace. He kicked them off, and practically tore off his top even as he wiggled out of his underwear, his erection was plainly visible now, Lilly smiled as she saw it, a sensuous look in her eyes. She stalked forwards, her hand reached out, her palm gently touching the head of his cock as her hands closed around his shift. Alex moaned, and she adjusted her grip, sliding her hands around until they had wrapped about his shaft. Then, she started to pleasure him as she had done before, rubbing back and forth, driving up his sensitivity. But this time, he wasn't going to just sit here and let things be done to him. Alex pressed forwards, pushing her gently but firmly into the far wall, the closeness of their bodies made his skin tingle, and he could feel the heat of her skin against his own. The smell of her hair was in his nose. As she continued to toy with his cock, each touch making it jerk with desire, his hands moved to her chest. Her skin felt warm and yielding, her breasts were firm, but soft to the touch. Not quite the same as Clara's. His fingers traced a pattern on her skin, and he pressed closer, their tightness making his blood pulse with desire.

"Ah!" She moaned suddenly, as he bent down, gently closing his teeth around her right breast, catching her nipple, and gently but firmly stimulating it with his tongue and lips. He sucked and licked her, and used his teeth as well, and Lilly started to buck slightly, her back arching in the pleasure.

Lilly let go of his cock then, spreading her legs slightly in invitation. He could see that her womanhood was drenched now. Alex felt his breath catching in his throat, the head of his did was pressed against Lilly's womanhood, her labia yawned open, allowing him entrance, and he pressed forwards. His eyes half shut as he felt himself sink into her, her pussy closed around him, almost seeming to grip his shaft. The feeling was intense. His legs and arms were tingling. Blood rushed through him, and he thrust forwards, driving her into the wall against, even as his hands continued to play with her breasts, and his head rose until he was eye to eye with her. Lilly was panting, gasping in time with his thrusts. The two of them were lucked together, moving in a slow but gradually quickening pattern as she ground herself against his cock, her pussy clenching around him, making each thrust more and more pleasurable than then the last. She moved with him, using her body to entice him deeper, matching his rhythm, and making it better and better for the two of them.

Alex had always known, of course, that sex was a skill. You didn't naturally know how to have sex, except at the most basic level. You had to practice, refine your timing, your movements, your ability to read your partner. All of these things took practice. Until now, he'd only had sex with Clara, who was like him, a newcomer to the game. But Lilly? Oh, Lilly knew what she was doing. The feeling of penetration made his toes curl, she leaned into it, then dancing away, almost like a game, her body motions making his cock twitch and stiffen. Her arms were around him, drawing him deeper into her, her legs were spread, inviting. The feel of her womanhood around his member was impossible to describe, he felt like he should have cum in minutes, but she was able to make it last. Teasing him, leading him. Sometimes, she was frantic, fucking him with all of her ability, driving him to the very edge of orgasm. But then, she would relax, bringing them into a slower pattern, letting him recover.

Alex realised he was moaning, each thrust was like a bolt of lightning through his every nerve. His skin was on fire, his cock was harder than it had ever been before. She had driven him to his very limit. The world had shrunk, becoming only the two of them. The friction of her skin against his made his spine crawl. The sound of her long moans and short groans matched his own. Slowly, he could feel the climax building within his gut, spreading to his loins, a sense of tightness and heat which he had never equalled before. Lilly seemed to know from the motions of her body, her grinding became more frantic, the motion sending shockwaves radiating through him, as she took him deeper into herself, her womanhood gripped him tightly, rubbing against him from all angles as he withdrew and then thrust again, each time, coming closer and closer to that moment of release.

Suddenly, he came. His cock shuddered, and Alex loosed a long and primal groan as he felt the seed flowing through his member and explode from his tip. Lilly gasped, the motion setting her off as well. Se climaxed, her body jerking, her womanhood closing on his cock, seemingly intent on milking him for even more of his cum.

After one moment which seemed like an eternity, Alex pulled out. He was heaving for air, his skin speckled with sweat. Lilly was equally thus, with the addition of his seed spilling down her legs, and dripping from the slit of her pussy.

"That was..." Alex gasped. "Holy shit..."

"That's what you get with practice." She winked at him. "In time, you and Clara might be able to do that too. Just to give you something to aim for in the future, you know."

"Lilly, I came inside you..."

"Oh, don't be so dramatic." She laughed. "Did you really think I was going to intentionally go out and find a way to become a sex slave for a day and then not take pills beforehand in case I got fucked? I'm just glad it wasn't wasted. You weren't too bad for a newbie either. Keep practising."

Alex took a deep breath. His heart was pounding, and the afterglow was making it hard for him to focus. Maybe it was the confidence born of what had just happened, but he had an idea, and plunged ahead with it before he could think again.

"Hey, Lilly? Listen, I could use some help for the rest of the week if you're up for it. Like, general help and support. Setting things up, talking to people, recommendations, that sort of thing. If you had the time, would you mind helping?"

"Hmmm..." Lilly seemed to think it over. She was heaving as well, and her body was slick with sweat. "Well, I do clearly need to get washed and cleaned up now, instead of just heading home, so I suppose I can do it with a few conditions."

"What conditions are you thinking of?"

"Well, firstly, I want to stay here for the next few days. You and Clara can have the bed, I'll sleep on the sofa. Secondly, I want to be included in any fun games the two of you might share, if I want to be. And thirdly...Thirdly, if at the end of the week, Clara decides she wants to keep doing this, I want a threesome with the two of you."

Alex blanked for a moment at that, Lilly grinned at the look of incomprehension on his face.

"Not only that." Lilly went on. "But during said threesome, I want you to fuck me, not just focus on Clara. I'll make sure you both feel good, and you can show me if you have gotten any better by then. That sound good to you, Alex? Oh, and Clara has to agree to these conditions as well, naturally."

"I..." Alex paused for a moment, looking into her eyes. Then, he slowly nodded, feeling his confidence return. "If Clara is okay with it, then I agree."