@Calum5SOS/ Twitter

5SOS' Calum Frees His Nipple In This Saucy Pic

Let them loose.

Rihanna did it, Rumer Willis did it, and now... 5 Seconds Of Summer? It seems like everyone is freeing their nipples lately, and now Calum Hood is onboard.

If you don't remember a month or two ago, Rihanna was banned from Instagram (I know, right?) for being topless. She joined Bruce Willis' daughter in a movement called #FreeTheNipple, where Rumer walked around New York City without a shirt. After all, it's legal there, and if a boy can walk around shirtless, why can't a girl? Notice how we don't have to blur this pic, but we'd have to if he were female.

So here we are, Calum. You're officially in. Free your nipples.

Oh, and happy birthday, Luke Hemmings!