If there is any doubt that Emmy Rossum is all grown up, check out her new Showtime series, "Shameless," in which she has some steamy sex scenes with co-star Justin Chatwin.

"We get so used to seeing the pretty version of sex, which doesn't look like any sex I have had ... the kind [with the] Hollywood girl with the blowout and she looks really pretty on the satin sheets. That doesn't really happen," the 24-year-old actress said at the Showtime session of the Television Critics Association in Pasadena, CA. "So, I think, when you are going to show real people and real feelings in a gritty situation to glamorize it would be foolish."

"Shameless" is the story of Frank Gallagher (William H. Macy), the alcoholic father of six smart kids, who might be better off without him. It's left to his eldest daughter Fiona (Rossum) to manage the family and make sure the bills are paid so the kids have the basics of life: food, lights and gas. Along the way, Fiona hooks up with Steve (Chatwin) for a little fun.

Emmy, who tells ETonline that she was the last one cast, says it was a relief when she discovered that she would be working with Justin, because the two previously had done a movie, 'Dragonball Evolution' together and were actually close friends. She says it has really helped because in "Shameless" they get very close.

"During our love scenes, especially one you will see later on, which takes place in a swimming pool, we are literally wearing nothing," she says. "He has a sock on and I have this thing that I invented with the wardrobe and makeup departments that I like to call the 'vag patch.' It is a strip of rubbery stuff that gets adhered to you. Like a triangle. We are in very close proximity. I remember for the pilot he said he would like to fill his with sand in case anything happened, it would hold everything down. We have a lot of fun and we laugh a lot. We are very comfortable with each other."

To check out "Shameless," tune in to Showtime Sunday nights at 10 p.m.

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