On "The Voice," co-mentors Blake Shelton and Adam Levine act as best buddies and frequent foils, often trading bromantic compliments and viscous barbs within the course of the same episode.
But off-screen, they kid around just as much, if not more. In a video update he sent to PEOPLE.com on Thursday, Blake Shelton revealed just how far their antics go.
Shelton began the video by answering fanmail in his driveway, but he eventually got around to reading this question from a woman named Debbie in California: "Are you and Adam really as competitive as you act like you are, and does he rub it in when he beats you at anything?"
His response? Shelton hollered "Hit it!" to someone off-screen, and his garage door slowly opened to reveal a larger-than-life copy of Adam Levine's "Sexiest Man Alive" People magazine cover, which towered over Shelton.
"Ladies and gentlemen, today I received a package from Adam Levine, and I think this answers [Debbie's] question," said Shelton.
He ended the video by adding, "This is why Adam Levine is a complete jackass. And it's also why I love him so much."