Shawn Mendes tells James Corden he'd drop $500 on Bieber's boxers during 'Carpool Karaoke'

James Corden must have decided it was time Shawn Mendes started confessing. And once he did during Monday's "Carpool Karaoke," there was nothing holding the Canadian pop star back.

In addition to singing his own hits like Mercy, There's Nothing Holdin' Me Back and In My Blood, Mendes talked about finally moving out from under his parents' roof.

The 19-year-old said it was an adjustment at first because "cooking for yourself and cleaning your house just sucks." At least his mom is kind enough to still help out... and do his laundry.

Speaking of laundry, Corden told his passenger that Justin Bieber wears a new pair of underwear every day, something the Biebs copped to during his "Carpool Karaoke" in 2015. How much would Mendes fork over for a pair of J.B.'s second-hand drawers? $500 maximum, it turns out. As for a pair of Corden's? Zilch. "I'd pay not to have a pair of your underpants," said Mendes, breaking it to his host.

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The Stiches singer, who admittedly doesn't even honk, tried his hand at having road rage and yelled at a random car while the pair were driving. For Mendes, it was a lose-lose sitch. He said the yelling didn't feel good, and he admitted he doesn't think he and Corden would fare well in a confrontation on the streets.

"I am not confident in getting in a fight with you," he said, predicting Corden would be no help in a brawl. "We would just have to get out and hug them."

Would Corden be any better on the ice? Turns out no. After seeing Mendes' hockey skills at a rink, Corden quickly realizes their friendly game of hockey was "a mistake."

See the duo's eventful ride in the clip above.

Contributing: Jayme Deerwester

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