Charlie Sheen Talks Feud With Rihanna, Disses Costars Jennifer Grey, Selma Blair, Jenny McCarthy

This man holds a grudge. Charlie Sheen talked about his long-ago feud with Rihanna, and rated his former costars, dissing Ferris Bueller costar Jennifer Grey, during an appearance on Watch What Happens Live on Wednesday, January 11. Watch all Sheen's cutting remarks in the video above!

The Two and a Half Men alum, who was promoting his new film Mad Families, was asked by host Andy Cohen about a Twitter feud he had with Rihanna almost three years ago.

Charlie Sheen on 'Watch What Happens Live'
Charlie Sheen on 'Watch What Happens Live.' Watch What Happens Live/bravotv.com

"Oh, that bitch," Sheen, 51, replied as fellow guest Craig Robinson shook his head and said, "No, no, no."

"I think you just made it worse," Cohen added.

"No, she abandoned common courtesy and common sense," Sheen added.

The pair's bad blood happened after Sheen was at a restaurant celebrating the birthday of his then-fiancée, Scottine Sheen (formerly Brett Rossi), when they saw the "Work" singer.

The former Anger Management star explained in a series of tweets in May 2014 that he sent a request to Rihanna's table asking if he could introduce Scottine, who was a huge fan, to the pop star.

Rihanna refused, and Sheen was told the reason was that there were too many paparazzi outside.

His fiancée was hurt and Sheen, who noted that he always takes time to meet fans, tweeted, "See ya on the way down…and actually, it was a pleasure NOT meeting you. Clearly we have NOTHING in common when it comes to respect for those who've gone before you. I'm guessing you needed those precious 84 seconds to situate that bad wig before you left the restaurant."

Rihanna responded by changing her Twitter banner to a pic of her signing an autograph for a fan, with Sheen's head superimposed on top of the fan's body.

Sheen wasn't in the mood to pull any punches during his appearance on WWHL, dissing his Ferris Bueller's Day Off costar Grey after Cohen played a clip of the iconic 1986 film. "Talk about a nose job ruining a career," he remarked.

He also didn't hold back about some of his other costars during a game of Plead the Fifth.

After answering a question about the craziest place he'd had sex (watch the video above to find out where it was), Sheen was asked to rank some former costars from favorite to least favorite to work with, with Cohen listing Selma Blair, Lindsay Lohan, Jenny McCarthy and Heather Locklear.

"Heather and then Heather," he said of his Spin City costar.

"Lindsay's a trip. She's work but she's cool. She's fun to look at," Sheen said of his Scary Movie 5 costar.

Of Blair (who was written out of Anger Management after feuding with Sheen) and McCarthy (Sheen's Two and a Half Men love interest, who criticized him after he revealed his HIV diagnosis), he said, "I'd like to mash those two together and then kick them to the curb. They deserve each other."

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