Could you please help!

This is from "what happens in Las Vegas...", right after Lauren gives Brody a big kiss in the club, the song goes like,
"I'm leaving with you boy, what we gonna do..."

Who sings this song??
Does anyone know?

if anybody wants to listen to the song, it's in this video:
Birthday Kisses | Video | The Hills: What Happens In Vegas... (Full Ep. 309) | MTV
starting at about 5.59

edit... btw.. this question was also posted in the other hills thread, no solution yet

Thank you, Steena

I wish someone could come up with the answer!!!