Mark waited for his father to go to work, then got up and went down the hall to his sister’s room, after retrieving his day pack from his closet. He knocked on her door and waited.

“Come in.” she called out. “I’m still in bed.”

“Good morning, Jen.” he said pleasantly, coming in and closing the door. “Remember you lost that bet yesterday? Well, we have the whole house to ourselves for the whole day, and I want to get started.”

“Right now?” she asked, her eyes widening in surprise. “I thought I would at least get to get up and shower and eat first.” She had lost a bet to her brother yesterday, a bet that involved the loser being a slave to the winner for the day.

“Sorry, I have a ton of plans for us today, and I want an early start.” he smiled. He grabbed the covers and pulled them down to the foot of the bed with one swift motion. “Come on, up!”

“Mark!” she gasped, covering her breasts with her arms, even tho her oversized T-Shirt covered her perfectly modestly.

“Call me Master.” he smiled at her. “And give me the shirt.”

“Mark! You can’t-” she protested, but he pointed his finger at her and cut her off with a stern look..

“You agreed to be my slave, Jen. A slave obeys her Master or she gets punished. Now give me that shirt!”

“Mark! You can’t mean this! I’m your sister!” she said, still sitting there in shock. “I’m not giving you my shirt. All I have on underneath it is my bra and panties.”

“Punishment, then.” Mark said, the smile fading from his face. He reached out and grabbed her upper arm, pulling her over his lap as he sat down on her bed beside her.

“Mark! Stop it!” she cried out. She found herself sprawled over her brother’s legs before she even knew what was happening. She struggled against him, but his arm lay across the small of her back, easily holding her in place. “Mark! Stop it!”

“Are you going to be a good little slave and obey me, or do I have to spank you?” he asked. His free hand caressed her panty clad ass cheeks boldly.

“Spank me?” she asked, sounding confused. “Mark, stop touching me like that!” She tried to squirm her butt out from under his hand, to no avail. “Mark, stop it!”

His hand lifted and fell quickly, slapping her far cheek with a loud sound. She wailed out lout, more from shock than pain. Their parents had never used spanking as a punishment on either one of them.

“Mark, wait! I’ll do it!” she cried. “Yes! Please! I’ll be a good little slave!”

“Better.” he said, pushing her legs to the floor. He moved her upper body so that she was kneeling in front of him as he sat there. “Take off your shirt, or it’s more spanking.”

She had tears rolling down her cheeks, but she crossed her arms and grabbed the hem of the T-Shirt. “Why are you doing this?”

“Off, I said!” He smiled as she lifted it up and slowly exposed herself to him, dropping it to the floor.

“You’re a beautiful girl, Jen.” he said, looking her up and down. “That’s why I’m doing this.”

“But I’m your sister!” she said. “You’re not supposed to be looking at me like this.”

“You’re not my sister today, Jen. You’re my slave.” he said. “Take the bra off for me, too.”

“Just because I’m your slave doesn’t make me not your sister.” she said. “You’re not supposed to make me do stuff like this.” She reached behind her back with one hand and unsnapped the clasp.

“It’s because you’re my sister that I’m doing this.” he said. “Come on. Show ’em to me!”

“No, Mark!” she wept, crossing her arms over her chest. “Please don’t make me do this! I’m so ashamed!”

“Jen, look up at me.” he said softly. He looked straight into her eyes and smiled. “All that shame you feel is making you sexy, little sister. It’s making my cock harder than it’s ever been before.”

“Don’t say that.” she whispered, looking down at the floor again.

“It’s true. Slave.” he said. “Now, drop that bra and show me your titties”

She began sobbing openly, but she reached her hands up and pulled the bra straps off her shoulders, pulling her hands free and dropping it on her shirt.

“Chest out, and look at me, Jen.” he said strongly, so she squared her shoulders and looked him in the eye again, defiantly.

“Good girl.” he said condescendingly. “That’s a good little slave! Now, reach up with both hands and squeeze them together for me! Act little the little slut we both know you want to be.”

“I don’t want to be a slut, Mark.” she told him truthfully, but she obeyed his command, taking both breasts in her hands and pushing them together. “I’m just doing this because you’re telling me to.”

She gasped out loud, her mouth open in shock as he pushed his shorts down to his knees, freeing his erection, which jutted proudly up from his neatly shaved groin. “Oh my God!” she said, under her breath. She had heard her friend’s descriptions, but had never seen one with her own eyes before.

“Do you like it, Jen?” Mark chuckled, seeing the expression on his sister’s face. “I want you to put it between your boobs. Lean up here and push them together around it.”

She looked up at him, startled at the request. “What?”

“You heard me! Get up here and titty fuck me!”

“Mark! I… I don’t…” she gasped, protesting. He reached out and grabbed her upper arms, pulling her closer.

“Come on, Jen! Act like a slut! That’s really what I want from you right now. Act like a slut and titty fuck me!!” he told her.

“Mark!” she pleaded. “I don’t know how! I’ve never done anything like this before! I’m not a slut, honest, I’m not!”

“It’s easy, Jen, you can do it.” he said confidently. “Just try it a little. Lean up here, push your tits together around my cock, and sort of ride them up and down. It won’t hurt; I promise. Just try it, okay?”

He let go of her, and she nodded. She took her breasts and pushed them together, then leaned down and let him thrust up between them. The head of it popped out of the top, and she was looking right down at it.

He held her by the shoulders and guided her motions, up and down, slow and steady.

“Look up at me, Jen.” he panted. “You’re doing it just right. It doesn’t hurt, does it?”

“No, it doesn’t hurt.” She smiled a little as she said it, and licked her lips.

“You know what I want when I ask you to act like a slut, don’t you, Jen?” he said, more a statement than a question.

“I… yes.” she admitted. He put his hands on her shoulders and got her to begin moving again.

“Why do you resist?” he asked. “You’re my slave for the day, right?”

“Because I’m not a slut!” she said strongly. “I didn’t know you were going to make me do THIS today, or I never would have agreed to the bet.”

“But you did, and this is what I want.” he explained. “Are you going to welsh on the bet?”

“No.” she said sullenly. “I’m no welsher. But I’m not a slut, either.”

“I agree. You are not a slut.” he said. “But I’m not asking you to BE a slut; I just want you to ACT like one. And you ARE my slave for the day.” he pointed out. “Tomorrow, you’re not my slave, so you won’t have to act like a slut. Simple.” He smiled at her. “Today, slave, I want you to act like my slut. Deal?”

“Deal.” she smiled, then a thought crossed her mind, and she frowned. “Mark, I’m a virgin. What about tomorrow?”

“What about it?”

“Will I still be a virgin tomorrow?” she asked.

“That’s depends on how much of a slut you are.” he replied. “Doesn’t it?”

She stopped moving on him again and looked right at him. “Mark, are you going to fuck me?” she asked, point blank. “Is that the point of this whole slave thing?”

“That depends on how much of a slut you are.” he repeated. “Doesn’t it?” He put his hands on her shoulders once more, this time pushing her lower. “Time to suck me off, slut.”

“Mark, I don’t… please, no, don’t make me!” she begged, putting her hands to either side of his waist and trying to push herself away.

“Jen, today, you are my sex slave! Take me in your mouth and suck me off!” he commanded, taking her head in both of his and and pushing her down to face it. “Do it, slave!”

She looked up away from his cock, pushing up with all her strength one last time to do it.

“You promise tomorrow everything will go back to normal?” she asked, pleading. “I’ll never have to do this again, right? Tomorrow everything will be the same as it was before? I can be a good girl again?”

“Of course.” he reassured her. “Just make sure you never lose a bet to be my slave again, that’s all.”

“You can be sure of that.” she said grimly, relaxing her arms. With only another little nudge from him, she looked back down at his cock, then opened her mouth and let it slip between her lips.

“Be a good little slut.” he told her. “No teeth, lots of sucking, and go as deep as you can every once in a while. Other than that, there’s no rules. Just have fun being my little slut for the day, Jen. Just have fun with it.”

She did as he said, and soon found she was enjoying the feel of him in her mouth. His fingers were twined in her hair, guiding the movement of her head somewhat, encouraging her to go a little deeper when she was on the down strokes, and caressing through the soft tresses while she was playing her tongue over the helmet shape.

His panting grew a little louder, his hand gripping a little tighter each time, and she wondered what it was going to be like when he did it in her mouth. What would it taste li-

Her mouth was flooded with hot, salty muskyness. It wasn’t so bad, but there sure seemed to be a lot of it. It filled her mouth and dripped out the corners of her lips.

“Swallow it!” he urged her. “Swallow it all like a good little slut!”

She saw no real objection, so she obeyed, drinking each spurt down easily after that. He let her go when he was done, collapsing backward onto her bed.

“Can I go take a shower now, Master?” she asked sarcastically, a moment later.

“Good job, slave.” he said, smiling and sitting up. He brought his legs up and sat cross legged, looking at her. “Stand up.”

She stood up and let him look at her. She wiped a drip of his come off her chin with two fingers.

“Give me your panties.” he said.

She bit her lip, a hesitant expression on her face, but she put her thumbs into the waistband at either hip.

“Please don’t take my virginity?” she pleaded, bending over to push her last remaining garment to the ground, then stepped out of them.

“That depends on you.” he said, taking the proffered panties and sniffing deeply at the gusset. Jen blushed at the look in his eyes when he smiled at her.

His eyes dropped to her groin, noting with delight that the little strip of hair sparsely adorning the mound between her legs.

“Please, Mark? Please don’t f-fuck me.” she begged. “Can I go take a shower instead?”

Mark took another sniff of her panties and smiled again. “You don’t need a shower yet.” he said, patting the bed next to him. “Come get on the bed with me.”

“Yes, Master.” she said, looking a little dejected that he hadn’t let her go. She suspected she knew what he wanted next, and she was more than a little curious, which was belied by the way she bounced up onto the bed next to him.

He made her face the foot of the bed, looking down at his feet, then had her straddle his chest, on all fours. “I’m going to know your secret taste, Jennifer. I’m going to taste every inch of you.”

Pulling her hips back with both hands, he put his mouth over her whole sex and wormed his tongue inside.

“Unngh, oh my God!” she cried out. “Ohmigod ohmigod!!!”

Her arms collapsed as brand new sensations flooded her nubile young body, and she found his cock stiffening against her cheek as her head came to rest in his lap. His mouth and tongue were working against her continuously, never stopping for an instant, and it was only a matter of minutes before the fourteen year old was having the very first orgasm of her young life.

As the spasms finally quit wracking her and the spasms stopped, she became aware that his cock was fully hard again. She lifted her head a little, and didn’t have to turn it very far to take him in her mouth again.

She knew what he liked this time, sucking and bobbing her head up and down all by herself. She was able to take it a little deeper in this position, too, and relished in the fact that she was almost able to get the whole thing down her throat.

“Play with my balls, too.” he suggested, so she reached down and gingerly took them in her palm, rolling them together. She felt them spasm and jerk in her hand, then he was coming again, squirting into her mouth. She swallowed it all easily this time, knowing what to expect, and found that she rather enjoyed the salty taste of him.

She let him slip out of her mouth and rested her forehead against his thigh. His hands were still caressing her nether regions, inside her thighs and over the little brown pucker of her asshole.

“Did you like that, slave?” he asked her, smiling. “Did you like the feel of my tongue inside you?”

“It was the best thing I ever felt.” she said truthfully. “Is it like that every time?”

“If its done right, it is.” he said. “I take great pride in giving women orgasms.”

“Well, you can be proud of that one, mon frere.” she sighed happily.

“Go take your shower now, slut, and get dressed in something sexy afterwards. We’re going to do a photo shoot after breakfast.”

“A… photshoot.” she said hesitantly, as she got up. “You’re going to… take pictures of me?”

“Oh yeah.” he smiled. “That will REALLY bring out the inner slut in you. I know it will.” He ogled her naked body, letting her see his eyes drop from her tits to her crotch.

“Mark… you can’t show them to anyone!” she said desperately, trying to hide her nudity with her hands. “Not anyone, ever!”

“I won’t.” he reassured her. When we’re done, I’ll give them all to you. You can delete them or whatever you want to do with them. I just want to do the photo shoot, that’s all.” He made a shoo-ing gesture with one hand. “Go take that shower!”

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