Rossee and Phelps. (Tim Whitby/Getty Images)

Michael Phelps may have won four gold and two silver medals at the London Olympic games, but he's leaving with arguably a more brag-worthy prize: his model girlfriend, Megan Rossee. Although the two have been dating for about five months, the statuesque blonde had gone largely unnoticed until she tweeted a photo of herself and the decorated swimmer celebrating his win with all of his gold medals at House of St. Barnabas on Sunday. Last night, they made their official debut on the red carpet at a Speedo event in London. While Rossee, a Hollywood cocktail waitress, certainly looked good on Phelps' arm, those who know her are warning that in the end she'll probably just break his heart.

Rossee and a friend dressed up for a LMFAO party in Vegas. (Instagram)

"She's desperate for her own fame — her career has been a slow-burner but this will certainly accelerate it," one source tells Radar Online of Rossee, 25, who reportedly has walked in fashion shows for Michael Kors and Betsey Johnson, and was recently in a music video for hip-hop producer-singer The-Dream. "Michael is like a puppy dog around Megan — he's completely in love with her. However, like any young girl hoping to make it in Hollywood, she's ambitious and knows that by associating herself with Michael she will get a lot of press herself."

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