Unlikely BFFs and singers Katy Perry and Rihanna are reportedly having a bit of a tiff right now over a man. And not in the usual way women fight over men in soap operas and sitcoms -- this stems from Rihanna letting abusive ex-boyfriend Chris Brown back in her life.

The two women bonded over a mutual respect and admiration for one another's music, but Katy doesn't want to sit idly by while Rihanna forgives Brown for beating the snot out of her. In fact, Perry is said to be so distraught by their renewed relationship that some obvious tension is occurring between the two women.

A source claims that Katy believes “Rihanna is making a huge mistake and doesn’t want to be part of it,” and has instead been hanging out with Kristen Stewart and Robert Pattinson.

If KStew and RPatz are your model of a stable relationship, up is down and right is wrong here. We also can't ignore the fact that Katy's taste in men leaves more than a little to be desired. But hey, at least her questionable judgment doesn't wind up on police blotters.

All that aside, it's been more a little nauseating to watch everyone rally around the Rihanna-Brown re-coupling lately, so it's good to know someone in RiRi's inner circle is all "dude, what the hell."

Fight the good fight, Katy. In the immortal words of the Blues Brothers, you're on a mission from God.