Rick Ross and K. Michelle have great chemistry, which was apparent when they performed 'If They Knew' on 'The Tonight Show Starring Jimmy Fallon' on Thursday night (Dec. 11). The dynamic duo grinded and flirted with each other throughout much of their sizzling hot performance.

Rozay, who looks slimmer than ever before, rocked a bright red MMG jacket, torn jeans and a white T-shirt with plenty of jewelry. K. Michelle was looking lovely in a sexy black-and-white outfit that surely got the attention of the men in the audience.

Backed by The Roots, along with a hype-man and DJ, Ross delivered his rhymes flawlessly, as his voice cut straight through the live instruments with great clarity. Somehow, despite the weight loss, he's retained that booming, husky voice that's made him famous.

'If They Knew' appears on Ross's seventh studio album, 'Hood Billionaire,' which dropped late last month.

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