There's no denying that these 13 celebrities are insanely attractive — but that doesn't necessarily mean they're perfect. We've noticed that there's one thing they all have in common: a naturally lopsided smile. See what we mean, starting with… "Game of Thrones" star Natalie Dormer. "I get accused of having a haughty smugness," Natalie told The Sunday Times in 2014 while promoting her role in the "The Hunger Games: Mockingjay — Part 1." But it's not her fault. "I have a lopsided mouth. I can't help it — I was born with it," she added. "It looks as if I am smirking. I have had my publicist tell me, 'Don't do that smile on the red carpet.' I'm, like, 'That's my smile.'" Keep clicking for more stars with natural-born smirks …
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Will Arnett
Will Arnett's mouth naturally pulls to his right when he smiles, but the resulting smirk actually suits the actor, who luckily gravitates toward characters who ooze humor and smugness.
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Katie Holmes
Online commenters have dubbed the signature asymmetrical grin that Katie Holmes made famous back during her "Dawson's Creek" days the "half smile."
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John Mayer
John Mayer's epic guitar-playing "O" face may be his most famous facial expression, but his always-slightly-up-and-to-the-left casual smile will be what you notice from now on.
Kristen Stewart
It's a rare treat when Kristen Stewart flashes a smile, and we absolutely love it when she graces us with one of those naturally left-leaning grins … because she kind of makes us feel like she's channeling Elvis Presley.
Andy Samberg
Andy Samberg's lips naturally pull his mouth up to his left, making the comedian look like he's about to crack a joke every time he smiles.
Alicia Keys
Sometimes, we think Alicia Keys is judging us. Then we realize nope, it's just her trademark all-knowing smirk, which comes courtesy of her naturally lopsided smile.
Lamar Odom
Whenever Lamar Odom cracks a smile, his mouth naturally favors the right side of his face, which lends the former Mr. Khloe Kardashian an air of easygoing humor.
Drew Barrymore
Drew Barrymore is the first to admit she has a slightly crooked smile. In fact, she once vowed she would "learn how to stop talking out of the side of my mouth," she told Elle, in order to nail the role of Edith "Little Edie" Bouvier Beale in 2009's "Grey Gardens."
Milo Ventimiglia
In 2006, Milo Ventimiglia explained to USA Today that his self-described "crooked" mouth is the result of a birth defect involving dead nerves that cause his lower lip to lie limp. His former girlfriend and "Heroes" co-star Hayden Panettiere told the newspaper how much she liked it. "It's so cute," she said. "It's a flaw, and I hate perfection more than anything in the world."
Kaley Cuoco-Sweeting
Though Kaley Cuoco-Sweeting often tries to put on a serious face when she hits a red carpet, we prefer it when she smiles. Her naturally right-leaning mouth makes her perpetually look like she's in on every joke.
Lorde
Lorde's choice of deep purple lipstick shows off her slightly asymmetrical smile, which lends her just the slightest hint of a natural smirk.
Dermot Mulroney
Dermot Mulroney's slightly askew smile has come in handy over the years, especially whenever he's played an outlaw in movies including 1988's "Young Guns" and 1994's "Bad Girls." But it's not the only noticeable facial feature that helps him look rough 'n' tough: Dermot also has a scar above his lip. "It's always been there," he told the Chicago Sun-Times' Splash magazine. "It certainly has its place on my face, right below my right nostril. That's where it belongs."