A/N Third time I've updated tonight. Sorry for the previous two chapters I know they were short but it was the introduction from here on I plan on making them longer.

Two weeks later

Early morning, Sebastian shoved another few shirts into his suitcase. He wanted to get out of the house before Kathryn saw him. He didn't need her bitchyness right now. Sebastian was off to Australia to visit Matthew and his mother.

Sebastian opened his door, it creaked suddenly he stopped.

"Going somewhere without me are we Valmont?"

"Yes" Sebastian continued on his way.

"I'll meet you down there, my luggage has already been loaded into the car just give me a second to grab something" Kathryn smiled at him.

"What? Your not coming Kathryn, there's no need" Sebastian glared at her.

"I'm not spending my Summer vacation sitting here by my lonesome, besides I haven't been to Australia in awhile" Kathryn started to make her way down to the limosine.

"Kathryn I said no, your not coming at that's that" He pushed her back and made his way outside, Kathryn running after him.

"Like hell I'm staying home Valmont, I'm coming with you and you can't stop me, remember that private jet is not just yours, I have as much right to use it as you do" Kathryn stated.

Sebastian sighed and decided to let her come after much arguing, he got into the car and sat next to his brunette bitchy sister.

"I haven't seen your mother in awhile either Sebastian, I'm sure she'll be happy to see me" Kathryn smirked at her gorgeous step-brother.

Kathryn had met Sebastian's mother on numerous occassions. Sebastian's mum loved Kathryn, she was pretty much the daughter she never had.

"Sure Kathryn if you think so" Sebastian thought he'd agree with her just to make the trip to the airport pleasant.

"Here we are Master Sebastian and Ms Merteuil" The driver opened the car door to let the pair out.

The luggage was loaded onto the Valmont-Merteuil private jet as Sebastian and Kathryn got on board.

"Sebastian?" Kathryn asked before continuing with her question. "Why did you never tell me about him? About Matthew I mean?"

Sebastian fiddled with his fingers.

"I don't know, it just never came to mind, really we aren't that close. We've spent probably all of 6 years together. We may be identical twins but I don't really consider him a brother. My mother called though and insisted I see him, it's been quite awhile" Sebastian kept his gaze outside the plan window.

Kathryn moved closer to him and put her hand on top of his, as if to comfort him.

Sebastian kissed her forehead. "Kate?" He started. "Promise me you won't try anything with him" He murmered to her as she rested her head on his chest.

"Jealous are we Valmont?" She giggled as she kissed his cheek.

"Not jealous, not jealous at all, worried" Sebastian half smiled kissing Kathryn back but on her lips.

The kiss soon intensified. Soon their hands were all over each others bodies. Kathryn's mind was racing at a million miles an hour. His hands groped away at her breasts as she kissed down his neck. Sebastian moved his hand up her dress and rubbed her through her panties. "Sebastian" Kathryn moaned, un-zipping Sebastian's pants. She placed his hardening erection in her hands and grabbed it hard, but not so it would hurt him. Sebastian swallowed thickly, he wanted Kathryn. His fingers moved inside of her rapidly as he could feel her muscles tighten. "Oh, fuck" She groaned. In a moment of intensity she grabbed Sebastian fiercly. He moaned suddenly, a little bit more and he would certainly come. "Kathryn..oh fuck" Sebastian placed his thumb on her clit and rubbed her still inside fingering her. That was it for Kathryn, she tensed, her back arched and her head tilted back, she came. As soon as she did her grip tightened around Sebastian's erection, when it did Sebastian couldn't handle it and he came, luckily for both him and Kathryn he didn't get them and landed on the seat infront of them. He smirked at her and kissed her forehead. She breahted heavily before resting her head against his shoulder, she felt her self drift to sleep. "Kathryn, I love you" He said, not sure whether she heard or not because she didn't reply.

As they got off there plane a black limosine much like their one back in New York was awaiting them. Sebastian's mother was rich much like his father. She was a successful business woman, what made it better was her husband who was also very successful, making them all the richer.

The driver got out and opened the door to let Sebastian and Kathryn in. Sebastian got inside surprised to see his mother, his brother and his step-dad. After Sebastian had seated Kathryn got inside.

"Kathryn? I didn't know you were coming" Renee, Sebastian's mother said.

"Hello Mrs Valmont-Dallas" Kathryn greeted her.

"Please Kathryn dear, you know to call me Renee" Renee smiled at Kathryn.

Sebastian shifted un easily in his seat as the car drove off.

"Sebastian aren't you going to introduce me?" Kathryn asked, slightly kicking her step-brother.

"Oh yes, Matthew and Paul this is my step-sister Kathryn, she decided to come along to Australia with me, Kathryn this is my brother Matthew and my Step-father Paul" He made hand gestures to introduce them.

"It's nice to meet you Kathryn" Paul stated as he shook her hand.

Kathryn smiled and politely shook his hand back.

"Like wise" Matthew said, just smiling at the beautiful slim brunette before him.

"Kathryn will you be staying with us?" Renee asked.

Kathryn gave one of her fake smiles. "If that's okay with you Mrs- uh I mean Renee"

Sebastian glared at her, he knew her act was fake.

The car soon pulled to a halt as they stopped at the Dallas mansion.

They all piled out of the lengthy limosine and follwed Paul into the large mansion.

"Sebastian, you remember the way around here, why don't you go show Kathryn to one of the guest rooms, take Matthew with you" Sebastian's mother gave him a kiss on the cheek and smiled.

Sebastian's mother was one of only two women he cared about in his life. Kathryn was the other. He took Kathryn's hand and they both followed Matthew up the stairs.

"Kathryn, would you like the room across from me or Sebastian?" Matthew smiled playfully, truly a Valmont.

Kathryn kept her good girl act. "I think it's best to be close to my brother, I'm quite new here and well I wouldn't want to be lost" She patted Matthew on the back politely. One of the doorman carried Kathryn's bag into the beautiful white and gold room.

At the dinner table it was quiet so Renee started to talk about things.

"Sebastian how are you doing at school?" She cut her chicken and placed it in her motuh, chewing graefully if that was possible.

Sebastian's mother was beautiful, Kathryn could see where he got his blue eyes and his blonde hair from. Much like Sebastian his mother had long golden blonde hair with slightly darker blue eyes then Sebastian.

"Good I suppose, doesn't trouble me, I always have people helping me with my school work" He gave Kathryn a look and a smile they shared. Only she knew what he meant.

"And Kathryn how are you doing dear?" Sebastian's mother smiled up at her.

"As far as I can say good, it's hard being the Student Body President, and so many presidents of other clubs, but I enjoy it" Kathryn played with her salad, it didn't really matter whether she was going to eat it or not, she was only going to throw it up anyway later.

"I'm glad to hear that" Renee said.

The table went quiet until Matthew spoke.

"Kathryn do you have a boyfriend?"

Kathryn gave a look to Sebastian. "I did, unfortunately he broke up with me a few weeks ago"

"Oh I'm sorry to hear that" Matthew's Australian/American accent blended together, only to make him that much more likeable.

"Something wrong with your salad?" Paul asked Kathryn.

Kathryn didn't know what to say. "Uh no, I-I-I'm just not hungry" She musted up.

"Kathryn you didn't eat on the plane at all how can you not be hungry?" Sebastain smiled coyly at her.

Kathryn shot Sebastian an evil glare. "I'm quite tired actually do you mind if I excuse myself and go up to bed?"

"Oh no of course not dear go ahead" Sebastian's mother smiled at her lovingly, Kathryn didn't get those looks from her mother.

Late that night the door to Kathryn's room opened. Kathryn didn't notice until they shut the door.

"Who's there?" She whispered.

"Sebastian" He said walking to Kathryn's bed and laying nex to her. "I couldn't sleep"

"Can you ever sleep Valmont?" She replied without thinking.

He didn't say anything he just layed beside her.

"Your brother's hot" She musted up.

"He looks like me, meaning I'm hot" Sebastian laughed quietly.

"Except with a hot Australian accent, which you don't have Valmont, besides that he probably hasn't fucked as many girls as you making him oh so more delicious and tempting" She licked his lips.

"Fuck you, you bulimic whore" He said turning over.

"No affection tonight Valmont?"

He got up and left without saying goodnight.

Kathryn was up early, she was already downstairs and dressed by the time Sebastian had gotten down there.

"Hurry up Sebastian" She called out, they were going into Melbourne today, Kathryn wanted to check out the local shops.

Matthew appeared but Kathryn thought it was Sebastian.

"There you are Valmont, hurry up or I'll never touch you again" She smirked at him and pulled at his arm.

"Uh Kathryn, I'm over here" Sebastian said sliding on his glasses and smiling with his perfect pouty lips.

Kathryn soon realised she had mistaken Matthew for Sebastian, she let go.

"Seb is there something I don't know about you and Ms Merteuil?" Matthew said that with such grace.

Seb, Sebastian never let Kathryn call him Seb.

"No, she's my step-sister and a whore of one at that" He smiled at Kathryn fakely and walked outside to the awaiting car.

When they got back from Melbourne, the butler let them know that Renee and Paul had to fly to Malaysia for the night and won't be back till late tomorrow.

Matthew was all to used to this.

Kathryn went straight to her room and she supposed Sebastian was in his room writing in that faggot journal he kept.

When it got late someone walked in the door.

"Oh Valmont, making these visits nightly now are we?" She questioned not realising it was the wrong Valmont.

"Ha ha, I'm sorry to disappoint you Kathryn but I am Matthew not the famous Sebastian" He caressed Kathryn's cheek lovingly.

Kathryn felt like it was Sebastian, she wanted to jump him.

Matthew being a Valmont had the same urge as Kathryn, before Kathryn new it her panties were off and she was hoisted up against a wall screaming and moaning and groaning. When the door opened Sebastian walked in shocked and hurt by Kathryn's sudden choice of events. "Kathryn" he sighed walking out to let them finish. Kathryn could see the hurt on his face. She knew it was wrong, yet she kept going, she kept the other Valmont inside of her, secretly imagining it was Sebastian and not Matthew, secretly wish it was her Sebastian screaming her name. Because after all she was his Kathryn.

She remember the night on the plane when he had thought she wasn't awake and he whispered "I love you" to her. She all of a sudden felt guilty. Guilt wasn't an emotion Kathryn usually felt.