Charlize Theron says playing her character in Young Adult "felt so wrong".

The 36-year-old actress is starring alongside Patrick Wilson in the upcoming comedy-drama. Charlize plays divorced woman Mavis Gary, who returns to her small hometown to win back her happily married high school sweetheart, portrayed by Patrick.

Charlize said it was fun playing the wayward character.

"It felt so wrong. I felt like I was eating cake three times a day and nobody was telling me I can't," she told Extra.

Charlize was initially unsure about the Young Adult script. She admits it was director Jason Reitman's involvement that persuaded her to join the cast.

"I think the first time I read it I responded to it the way people are responding to watching the movie. Really uncomfortable and really unsettled, and just kind of cringe-worthy" she giggled. "The thing that really sold it to me was Jason Reitman. I just really wanted to work with Jason. I saw great potential in this character with him at the helm."

Despite feeling a bit of disdain towards her character at first, Charlize was ultimately won over. The stunning star says she can't help but be interested by the complexities of Mavis' personality.

"You know when you're driving, this is such a bad thing to say, but when you're driving on the freeway and there's a car accident and you have to stop and look over, and we all do it and it's horrible, but we all do it right? That's Mavis, welcome to Mavis. She's that accident," she smiled.

"I think that she is a character that surprises you, and that there is something endearing about her unattractive qualities."