Kristen Stewart kicks off her shoes and plays a drinking game with Jimmy Fallon

Kristen Stewart was apparently in a party mood during her appearance on "Late Night With Jimmy Fallon" Wednesday.

After taking care of business promoting "The Twilight Saga: Breaking Dawn — Part 2," the talk show host convinced the typically guarded actress, 22, to stick around for a game of "Big Quarters" — a modified version of the classic drinking game in which they attempted to bounce enormous fake coins into a giant plastic cup. During the segment, K-Stew, who was wearing a little black dress, kicked off her four-inch heels and went barefoot. FYI, her toes were painted black.

[Related: Exclusive — Kristen Stewart and Robert Pattinson say they want to work together again]

The competition between Stewart and Fallon was playful. "I desperately want to beat you," she warned him. But it wasn't so easy. "I hate this game," Stewart, who was fidgety on stage, said after Fallon scored the first point and she had to chug a cup of beer. Still, she was a good sport and gulped down her beverage as the audience chanted, "Drink! Drink! Drink!" She later got revenge, and it was Fallon's turn to drink up. "That's real beer!" he announced after emptying his cup. "Yeah, it is," she replied. After 3 1/2 minutes — during which Stewart herself remarked "We're doing this for quite a long time!" — Fallon was crowned the Big Quarters king.

While Stewart had some light-hearted fun with Fallon, not all of the publicity that she's done for the movie has been easy. Earlier in the day, while being interviewed on the "Today" show, she was finally asked the question people have been wondering: Is she officially back together with her "Twilight" co-star Robert Pattinson? "Funny you mention that," Stewart replied. "I'm going to just let people watch whatever little movie they think our lives are. Keep 'em guessing, I always say."

[Related: Kristen Stewart breaks her silence about her relationship with Robert Pattinson]

As we noted, it's really not much of a guessing game. Since their brief split over the summer — when she was photographed kissing her married "Snow White and the Huntsman" director Rupert Sanders — Stewart and Pattinson have been photographed together on multiple occasions. And, yes, there was even PDA. Perhaps on their next dive bar date, they'll be photographed going head-to-head during a intense game of … Big Quarters.

Watch the LIVE red carpet premiere of "The Twilight Saga: Breaking Dawn — Part 2" on November 12 at 8 p.m. ET/5 p.m. PT exclusively on Yahoo!.

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