Justin Bieber Strips Down to His Underwear During Concert — See His Sexy Butt! (PHOTOS)

If you've always wanted to know what Justin Bieber's butt looks like (don't deny it!), you're in luck.

The pop singer stripped down during a January 18 concert in Nashville, Tennessee, according to Hollywood Life.

The Biebs showed off his sculpted bod to the lucky crowd as he pulled off his t-shirt, which can be seen in these fan photos.

He proceeded to perform onstage with sagging zebra-print pants that revealed his red boxer briefs.

Apparently, he has decided to strip during concerts in order to present a more grown-up and sexier persona. 

Maybe his new song should be changed from "Beauty and a Beat" to "Beauty and a Butt"!

Source: Hollywood Life, Instagram, Instagram