Justin Bieber Bares His Bieby Bum On Instagram!

                          
                            

Looks like somebody’s heating things up on Twitter!
Justin Bieber might be showing Selena Gomez what she’s missing out on, because earlier tonight, he uploaded a pic of his bare butt on Instagram!

With a caption that read, #moon, the Biebs tweeted out the pic (above)… and then deleted it!
However, it was already too late — fans all over the social networking site screencapped it and practically EXPLODED!

Bieber’s response after the deletion?