Tourmates and decade-long friends Demi Lovato and Nick Jonas did a round of Carpool Karaoke with James Corden on Monday's Late Late Show, and Lovato and Corden had some fun with Jonas' dating history (Miley Cyrus, then Selena Gomez, then Cyrus again, then Gomez again). Lovato and Jonas have clearly been friends for a long time, because she's hilariously comfortable making fun of him, and he just sits there and takes it.

It's not all roasting, though: they also sang some of Lovato and Jonas' songs, as well as Nick's brother Joe's song "Cake By the Ocean," before getting out of the car and busking on Hollywood Boulevard.

It's breezy, even by Carpool Karaoke standards. Lovato is very likable, even when she's having a coughing fit.

Nick Jonas, Demi Lovato and James Corden, <em>The Late Late Show</em>Nick Jonas, Demi Lovato and James Corden, The Late Late Show

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