Rob Latour / Rex USA 1 / 10
Rob Latour / Rex USA 1 / 10

Evangeline Lilly didn't really appreciate her "Best Butt Ever" cover of Women's Health's upcoming January/February 2014 issue.

The "Hobbit: The Desolation of Smaug" star, 34, stopped by Conan O'Brien's Conan show on Dec. 4 and admitted that she was unhappy with the mag.

PHOTOS: Lost stars: Then and now!

O'Brien, who broached the topic with Lilly, gave a brief description of the fitness magazine's cover: "They go, 'Best. Butt. Ever.' and they have an arrow going to your butt," he said, holding up the issue in question. "I'm just curious -- is that something they tell you before you do the shoot?"

PHOTOS: Lilly and other hot Canadians

Lilly retorted, "No!" The mom to 2-year-old son Kahekili asked, "Do you think I would have done the shoot if they said, 'Oh, by the way, we're gonna say 'Best Butt Ever!' and put a big arrow to your behind,'" as she signaled to her posterior. "You know, every woman is after a kind of classy image," she explained. "I didn't want T&A on my cover. It's a women's magazine, not Maxim."

PHOTOS: Best celebrity makeovers of 2013

The former "Lost" actress added that she later spoke to the magazine to express her displeasure over the butt/arrow addition. Lilly is not alone, however, in all this. Chris Hemsworth's hot (and pregnant again) wife Elsa Pataky was featured on Women's Health's June 2013 cover -- with the words "Great Butt!" and an arrow pointed to her sculpted backside.

The "Hobbit: The Desolation of Smaug" -- in which Lilly plays an elf named Tauriel -- hits theaters Dec. 13.


Top 13 celebs of 2013

Undressed 2013: The year in fashion faux pas

Best celeb bodies of 2013