It was Friday night and Sebastian was in Kathryn's bed. They haven't seen each other in a couple of weeks and Sebastian could feel how she craved his body. She was dating Riley Hammels but just to earn herself some name recognition. She only had sex with him once a week. Sebastian had his share of one night stands, he was Sebastian Valmont after all, but still it was the best with Kathryn. At around 4 o'clock AM as Sebastian was about to fall asleep Kathryn said to him:

"I have a suggestion I'd like you to consider."

"Sure thing, sis, we're already naked and in your, bed so ok."

"Ha Ha." Kathryn opened the a drawer in the dresser next to the bed, pulled out a business card and handed it to Sebastian.

"XLS Talent Agency? What am I supposed to do with it?"

"They're looking for someone for a car commercial, I want you to go an audition for it."

"Why?"

"Think about it Sebastian. In high school we ruled but now things are more complicated. It's not enough that we are rich, we need to be famous!"

"And this car commercial will make us famous?"

"That's one step."

"But even if I audition aren't the chances like a million to one?"

"Oh, my idiot brother! Don't you know me by now? The manager there is the father of a girl in Clarence I know. If you go, you get the part. Trust me."

"I don't know. I'm not sure I want it."

"I'll make it worth your while Sebastian. You know I will, don't you?"

"Sebastian's cock became instantly hard as he heard that."

"Just how…will you make it worth my while?"

Kathryn just smirked at him for a few seconds. And then shoved her tongue down his throat

Several weeks later Sebastian's commercial aired. It showed him driving around in a red convertible and talking on the car phone with several characters. 'Don't forget to pick up your brother from soccer practice', a woman says and a couple of seconds later Sebastian's character shows up at a soccer practice. 'Right on time', says the actor portraying his brother. At the end of the commercial an extremely attractive actress portraying his girlfriend enters the car and says: "Right on time, like always". Sebastian's voice over is heard saying: "When everybody's breathing down your neck, family, friends, girlfriend you've got one thing to depend on. The new Brolix. Always dependable."

The Friday after the commercial aired for the first time, Kathryn invited Sebastian to her bed. Of course she let anyone at her college know her brother was starring in a commercial which increased her popularity. She was in a good mood and Sebastian was thrilled to take advantage of that.

After a couple of hours they began to chat and Kathryn said: "I have a proposition for you. She took out a magazine from the dresser, flipped through it and showed the page to Sebastian. It was a bikini ad.

"Whoa, who's she?"

"Her name is Cheryl Mahone, she's a student at Clarence. She's in another sorority but we take a couple of classes together. As you can see she's a bikini model and she's recently broken up with her boyfriend. So sad. To make a long story short I want to...introduce you to her."

"You…want me to go out with..her? What the hell are you up to?"

"Nothing."

Sebastian just stared at her.

"This is the next step for us. You're now starring in a commercial but this is just the beginning. Dating a bikini model will make you and us and especially me just a little bit more famous."

Sebastian wasn't surprised that Kathryn was in fact just thinking of herself. He hesitated.

"Look Sebastian, just give her a call! What harm could one phone call do?"

Sebastian still hesitated. He didn't want to be a pawn in his step sister's plans and yet he was curious.

"Ok." He said.

Kathryn gave him the phone number and he chatted with Cheryl the next day. After his chat with Cheryl he talked to Kathryn.

"So did she sound nice?"

"Yup."

"And you made arrangements to ...get together?"

"Yes."

"Good." She said and smiled at him.

"Just on little thing."

"What?"

"She said she has this five-date rule."

"Five dates? As is five dates until ..."

"Yup.

"Well, well. You think you can handle it?"

"With a body like that she's worth the wait."

"So you'll be patient and wait?"

"You don't trust me?"

"I'm afraid you will fuck this up. Literally."

"Oh I will fuck this up after five dates. It's like four and a half more dates than usual, but I'll make it."

"This is serious, Sebastian, if you get involved with her it can be big for us, don't screw this up, please."

They continued to talk for a while and a couple of days later as Sebastian was getting ready for his first date with Cheryl, Kathryn showed up at his room.

"Is this what you're wearing?"

"No, I'm taking a shower now and then I'll decide what to wear. Would you please stop being such a tight ass?"

"I'm worried you won't be able, you know, control yourself, and screw this up."

"Don't worry, sis."

"Well I am worried so I thought I might, you know, take away some of that sexual energy of yours so you can concentrate on being nice."

"What do you mean?"

"You know...do it."

"You're kidding!"

"I am not!", she said, and took off her shirt. "Just a quickie and you'll be on your way."

"You're nuts!"

"Maybe I am but I think we should fuck now, are you sure that 'no' is your final answer?"

Sebastian didn't have to answer that. He could never turn down his step sister. By the time her tongue touched his he was very hard. He didn't like quickies. He preferred exploring his sister's body for hours at a time but Kathryn wanted a quickie at that moment and that all that mattered. Their cloths came off quickly. As they approached the bed she moaned to him: "You be on top, you'll cum quicker." Sebastian complied and after a couple of minutes when he was about to cum he asked her if she was about to cum to which she said: "Forget it idiot, just cum." He did and she got dressed before he was able to catch his breath. As she left his room she said: "Take a good long shower, I don't want her to smell my perfume on you."

He had a pleasant dinner with Cheryl and they made arrangements to watch a movie several days later. When he talked to Kathryn after the date she asked him: "So, was your sexual energy in control?"

"I was a perfect gentleman."

"I'm glad I could help. We'll do it again before your next date, ok?"

"Sure. Why don't you come by earlier so you can have your pleasure too."

"My pleasure isn't important, brother. It's just so you won't be obsessed with sex during your date."

"I realize that, but if it will be more intense, than the less sexual energy I'll have during my date. In fact let's do it in the shower, it'll save time."

Kathryn smirked at him. She knew he would take advantage of this opportunity. She agreed.

Several days later, before his second date with Cheryl, Kathryn joined him in the shower. She went down on him pleasuring him with her tongue and lips. It was awesome. The hot water poured on his body, Kathryn's hands were grabbing his ass tightly and Kathryn pleasured him like only she could. He wondered why they didn't do it more often in the shower. The pleasure grew more intense when he fucked her against the shower wall. He loved making her cum more than anything. When it was over she helped him pick out cloths for his second date with Cheryl. Their third date was scheduled for Sunday afternoon. Their parents were away so they had the house to themselves. Kathryn knocked on his door in the morning. She inquired about the development of his relationship with Cheryl and was pleased to hear things were going well. She then said:

"Well I'm free this morning so if there's anything you wanna do I'm up for it."

"Anything."

"Yup."

She smiled at him when he asked her to undress. When he was about to enter her body he said: "Hey sis, I want to you to say my name every time I thrust, K?"

"Anything you want, brother." She said.

She moaned his name the entire morning. By the time he started to get ready for his date with Cheryl he was exhausted. They had another pleasant date and kissed for the first time. For their forth date Sebastian suggested that Cheryl came over to his house and he'd cook dinner for them. Again he showered with Kathryn before his date and Kathryn left before Cheryl arrived.

Kathryn gave him some space before his crucial fifth date with Cheryl. It was set for a Saturday night. Their parents away and Kathryn was alone at the house studying while Sebastian was on his date with Cheryl. It was thrilling. Of course he had his share of hot girls but still, Cheryl was a bikini model! He explored every inch of her body during the two times he fucked her. He was in a very good mood when he returned home. As he got into bed his phone rang. It was Kathryn.

"So, you sealed the deal?" She asked.

"Yup. And it was awesome!" He replied.

They chatted for a couple of minutes and when they said good night to each other Kathryn said: "I'm in bed studying. I guess you're tired but if you want to drop by my room it's no problem. I'm naked."

"You're nuts."

"I'm not kidding."

"I'm going to sleep, good night, we'll talk in the morning."

But he couldn't fall asleep. Something bothered him. After a while he got out of bed and walked over to Kathryn's room in his boxers. He didn't knock before opening the door. Indeed Kathryn was in bed lying on her belly reading a book, naked.

"Well hello there." She said

"Did you know about Cherly's five-date rule before I called her the first time?" He asked

"Yes." Kathryn replied without hesitation.

"So all this was planned? All those sessions before my dates with her?"

"Pretty much."

"Fuck you! Why?"

"Well I hated the thought of sharing this body, I mean…"

"Don't bullshit me! You were taming me!"

"That right!" She said as she got out of bed and approached him. "I need to be in control of things."

"Fuck you."

"You knew what I was a about from the start, Sebastian! You know very well that everything I do, I do for my own interest. You're obsessed with sex and obsessed with me and especially obsessed about sex with me and yes I was using it for my advantage. Now, if you wanna, we can call the whole thing off and go our separate ways. Is that what you want?"

Sebastian just stood there, silent.

"I didn't think so!" Kathryn said. "Now, I'm going to kiss you and touch a little bit, and then I'll get down and you'll fuck me in your favorite doggie style position here on the floor. She began to kiss his neck and chest and slowly worked her way down. By the time she got down to his cock he was completely helpless. He let out a loud moan a she started to pleasure him. It didn't matter that a couple of hours before he fucked a bikini model. He was overcome by his lust to his step sister. When they were both on the floor she said to him: "God Sebastian the idea that you still want me while dating a bikini model that is like the biggest turn on ever!"

"Wow, you're so horny sis!" Sebastian said.

"I was thinking about you fucking that bikini model all night and that made me more horny than ever! I just had to fuck you tonight!"

As she said that, Sebastian thrust his cock into her body. Their moans were louder than ever and their pleasure grew more and more intense with every thrust. They did it in doggie style position on the floor and later moved over to the bed.

Several hours later, after their fourth time, they were still in bed together cuddled.

"This got to be the best night ever." Kathryn said.

"I agree." Sebastian replied. "That was like…wow there's no word for it."

"God we're so sick." Kathryn said. "The more people we have sex with, the more we wanna fuck each other."

"Yeah, we're sick." Sebastian replied and they both giggled. "So what happens now, Kath?"

"Now you get a few more commercials and become more recognized. Of course dating a bikini model will help and I will use my association with you and Cheryl to advance my goals."

"And what about us?"

"It will be tricky but we'll find a way to keep this going. This must go on Sebastian, I'm not giving this up. In fact, now that the stakes are higher you should be rewarded accordingly."

"I'm free next Tuesday morning. I want you in my room doing everything I want."

"Absolutely."

Sebastian was stunned. It was easier than he expected. "Thursday afternoon too." He said.

"No problem." Kathryn replied

Something new was about to begin