twenty one pilots's Josh Dun Speaks Briefly After Winning Grammy

(TMZ) - Josh Dun either didn't think Twenty One Pilots would win a Grammy, or he's just messing with TMZ ... but he insists he didn't give a thought to his underwear when he got dressed for the show.

TMZ caught up with Josh at Milk Studios for a big after-party, and he doesn't understand why people are making a big deal about a bunch of guys watching the Grammys together in their skivvies.

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