Disclaimer: I don't own life with Derek

One day.

It was regular day for Casey Macdonald or as regular as it can be with her menace of a stepbrother Derek, things weren't the same for her now though, even though she could hide it very well from everyone and cover it up with pointless fights with Derek, she had fallen in love after about a year of moving in with the Venturis with someone she would have never guessed it would be. Derek, her step brother that over time she has come to know and love, it was off limits and she knew that but oh the jealousy she always felt when he would bring a date home and whisper sweet nothings in the bimbos ear. Also Casey would never admit but she always thought that she was the one Derek should love, that she was the one that could take care of him, that she was the one Derek should whisper sweet nothings to.

But time and time again he would date another girl, that probably had the IQ of a shoe and Casey always thought that he was just trying to tease her, but every time Casey would also step aside let him do as he wanted, she didn't want Derek to know that everything he did with those girls that he would do the same to her and she didn't want him to know every time he has his girlfriend near her it makes her want to rip all of her hair out. She didn't want him suspicious of her behavior that was starting to change drastically since she couldn't take standing in the sidelines watching him date other girls that were not her; she needed to tell him soon before she could do something rash because of her strong feelings.

Casey finally got her chance. She and Derek were finally alone for the weekend since the rest of the Venturi/ Macdonald family were snowed in at a relatives house. She and Derek were watching T.V or rather he was watching T.V and she was enjoying his company, but he didn't necessarily know that part…yet. All was quiet, but then Derek suddenly turned to Casey. "Where is all this tolerance coming from? Why haven't you tried to take the remote from me and why are you always surrendering to our fights and letting me win? Are you sick or something?"

She could clearly see the confusion that was written all over his face and she thought of how cute he looked, his face was so innocent and his hair was in his usual wavy disarray, and she could smell his cologne. Oh how she wished that she could just close the gap between them and let her lips brush against his even if it was just for a brief moment, which was the only thing she desired at the moment, so she decided that, that was what she would do. "Derek if you haven't figured it out by now then let me show you" and with that being said she scooted closer to him and put her hand on his face then leaned in and softly pressed her lips to his soft ones.

Casey wasn't sure what to expect but it surely wasn't this. But what surprised her most was that he wasn't pushing her away, he was actually kissing her back and brushed his tongue against her bottom lip, begging for entrance. She obliged but soon pulled away and smiled at him, he smiled back. "You have no idea how long I have been wanting to do that" he smiled and his reply shocked her.

"Actually I think I do, I have always cared about you Casey but was afraid that you didn't reciprocate my feelings" wow she didn't even know that he knew what reciprocate meant yet the fact that he actually felt the same way about her as she did for him, since she was sure of his feelings she wanted to mess with him for a little bit.

"Derek Venturi I am shocked. How did you even know what reciprocate meant, more than that you even used it correctly in a sentence. How do explain yourself for the change?" he smiled at her then brought his mouth to her ear, kissed her right under her earlobe, which made her gasp in pleasure, then he brought it to her ear and whispered in a voice that made her heart flutter. "I have learned about a lot of things with you around. But I think it is time that you learned a few things from me." And with that being said he gently but firmly brought his mouth back down to hers and kissed her with all the pent up passion that he held for her all of these years, and to show her how much she really meant to him. She kissed him back with equally amount of force then once again pushed him away. He sighed then looked up at her.

"Don't worry we can finish this up later, but we need to figure out what we are going to tell the family and everyone at school, what will they think?" he spent a minute thinking about it then smiled his trademark grin. "Who cares? All that matters is that your mine and I'm yours, it's as simple as that, with no strings attached." She was surprised, Casey thought that it would surly be more difficult than that, but what he said did make perfect sense. She was happy she had her dream guy, that wrapped his muscular arms around her thin figure and they still sat there watching TV with each other just enjoying being in each others arms when Derek suddenly got smirk on his face and turned to look down at Casey.

"By the way, you do need to work on your kissing technique, it's a little rusty, when was the last time you had a boyfriend?" She looked at his smirk then immediately wanted to make it vanish from his gorgeous face. Casey glared at him then hit him on the shoulder with as much force as she could manage, she heard the grunt and the 'ow' that he muttered but she just sat there smiling widely, and triumphantly. Then she got off his lap and started to walk up the stairs but when she was in the middle of the stair case she turned to him. "That was for making fun of me, and also I wont kiss you till tomorrow, and don't give me that puppy dog pout, you brought I upon yourself." He muttered something unintelligible and then pouted again, "Why do you have to punish me so?" he whined.

She walked back down grabbed his shirt and pulled his face down to meet hers, he thought she was going to kiss him so he leaned in, but Casey had other plans, "Derek you should know that I never give up without a fight, so every time you make fun of me that is one day without kisses. So I think It would be wise if you just didn't make fun of me anymore" He grumbled then thought 'wow I think I rubbed off on her, she learned from all the pranks I gave her'. Then he thought of something that would most likely work on her. "But Casey I thought you loved me." He put on and adorable pout and looked back at her with hopeful eyes. She smiled and just said against his lips "Oh I do more than anything, but that doesn't change one single thing." And with that she pushed him away from her and ran up the stairs and into her room thinking 'I am so going to get him for all those nit twits he dated'.

My first life with Derek fan fic :) review and tell me what you think