In the first scene Regan Reese plays a dual role. First she is a prude in a hoodie making out with her boyfriend but not giving him any. Later he comes back to the house and is met by her "sister", who is Regan wearing the most white-trash yet sexy outfit I've seen in a while. She has cut up a pair of denim shorts until they're hardly more than a belt, and the same with a hot pink mesh top. She's the shameless slutty one, and starts rubbing herself in front of him as she questions why her sister holds out on him. After a few minutes they go at each other, and it's very hot. This is a scene that stands out in my mind long after watching it.
The rest of the movie is good but just couldn't compare to the opening. Well worth a rental.