In case you forget, they danced to the song "Everybody Knows" by Dustin Tavella and now Sel's starring in the singer's brand new music video!
Selena's cameo comes in at the 4:20 mark and surprisingly she's not poking fun of Bieber in her segment. She's actually convincing a girl to leave her d-bag boyfriend! Hmm, sound familiar?
Watch the entire thing above! The song and video are both SUPER catchy!