Justin Bieber climbed into James Corden's karaoke car on the Late Late Show last night (May 20) to sing his monster 2010 hit "Baby" and talk dirty underwear, swag and more.

"I gotta be honest, when I picked you up just now I didn't recognize you for a minute 'cause you had a top on," Corden jokes, obviously alluding to his chest-baring Calvin Klein ad campaign from earlier this year. Corden then asks if the designer sent Justin unlimited pairs of underwear — Bieb confirms they did, and that he only wears his white briefs once.   You could at least auction those man-panties off for charity, Justin!

Bieber and Corden then proceed to murder Ludacris' "Baby" verse, because Luda is the most fun karaoke choice ever (recommended, if you  want to bring the house down: "What's Your Fantasy," or his feature on Fergie's "Glamorous"). Corden grills Justin on the girl he's getting texts from, who we're guessing is Jayde Pierce ("Have you kissed her yet?" "No, you can't kiss a girl until marriage, everyone knows that.") The late-night host also asks that age-old question, "Do you ever listen to your own music while making love?" and points out the most absurdly over-the-top "Boyfriend" lyric: "Chillin by the fire while we eatin' fondue."

Justin's wearing the same gray hoodie he was sporting when he filled in on drums with the Late Late Show band, so we'll assume this was filmed the same day. Corden's providing a valuable assist on Justin's mission to reform his public image in 2015, and the singer's making some major strides — just by being the best-behaved version of his undeniably charming self.

You can check out the entire performance-slash-interview in the video above.

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