Kristen Stewart says she doesn't exercise or watch her diet.
"You should see my brother; he's, like, emaciated," the Twilight star, 19, tells the November issue of Allure. "We both just happen to be really skinny."
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But the actress doesn't think she looks good. She laments the way she appears on talk shows while promoting her vampire flicks. (New Moon hits theaters Nov. 20.)
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"It's all about those 10 minutes. You have to be funny and cute, and you have to promote the movie, and I don't know what else," she says. "You have to look hot or something. I don't know; I don't know."
Still, she's not doing much to improve her style.
"I go outside, and I'm wearing a funky T-shirt and my hair is dirty, and people say, 'What's wrong with her? She needs to invest in a hairbrush,'" she says.
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Stewart goes on, "I'm like, don't you get it? I'm not that girl! Like, I never was that girl. It's not like I was really clean-cut last year."
But that doesn't stop her from Googling herself to see what people think.
"The commenters are usually worse than the bloggers," she says. "I know what people say about me."
Stewart -- who got lost en route to her Allure interview at a Beverly Hills hotel -- says she'll check the internet later to "see what an idiot I looked like getting lost ... you just Google, 'Kristen Stewart, lost, directions.' Or put the date in. I can't believe I'm giving away how to Google me!"
In the same interview, Stewart refuses to discuss her relationships with Michael Angarano or costar Robert Pattinson, but touches on the "sexual dynamics" between her character, Bella, and Pattinson's Edward.
The two can't have sex on screen because it would turn Bella into a vampire.
"It's [more than] foreplay. Even though it does that so well -- it does a f---ing good job -- the buildup, is like, ridiculous. But it's all for the right reasons. You're so in her shoes that it's a vicarious experience. It's addictive," she says.