The star Tweeted, "I officially have Bieber Fever!!!" on Saturday night at the 2010 White House Correspondents' Dinner in Washington, D.C.
Justin himself declared himself a fan of Kim, too, Tweeting a picture of the pair with the caption, "Look its my girlfriend @kimkardashian."
Justin wasn't the only young star Kim met up with on Saturday night. She posted another Twitter photo of herself with Disney cutie Demi Lovato.
"Sweetest girl ever!" Kim Tweeted, adding later to Demi, "U are so beautiful! So glad we met."
However, when it came to her style at the D.C. dinner, Kim went old-school – she heated up the red carpet in a black-and-white vintage Valentino dress belonging to her mom, Kris Kardashian.
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