Justin Bieber -- Strips Down For Raunchy S&M-ish Photo Shoot

Justin Bieber became someone's bitch -- stripping down for a leather clad S&M styled shoot in the August issue of Interview Magazine.

The raunchy images were oddly paired with an interview conducted by Martha Stewart ... who last saw Biebs on his Comedy Central Roast.

Funny thing is ... we think they were going for a '50 Shades' kinda feeling, but Bieber's baby face in a leather mask just looks more like Batman's sidekick, Robin than he does Christian Grey.