Falling For My Roommate

Hey guys and girls this is my first really story so its probably going to suck. Just to clear something up this story is writing but what ever comes to my head and no where near real it is completely made up so dont get mad.
Also:
Liam and Miley are dating in the story.
Harry and Ariana are dating in the story.
Nick and Demi are dating in the story.
Mitchel and Emily are dating in the story.
Zac and Lily are dating in this story.
Tom and Taylor are dating in this story
Joe, Selena, David, and Sophia start off single in the story.
(I know I just changed it).
(I also you that most of these relationships aren't current I don't care as it's just a story so please don't hate).

Please comment with ideas or even tips on what you want to have happen in the story or how I can improve it or even if you want to see more characters I will take all the help I can get.

(AN: Please don't expect me to play all the characters as the main two are Selena and David I will be the others if and when I need to as I am the only one doing this story. However if someone would like to partner up with me I would happily welcome it as I am starting to think I have gotten myself in way over my head.)

Warning this story is for mature readers 18+ it will have sexual content bad language very low violence if any and pictures.

Thanks very one and hope you enjoy it.