Update (1/17): Charlie Sheen just can't stop trying to get Rihanna's attention, though the Anti singer remains unmoved. He just tweeted an apology to Rih, who probably had no idea that he'd insulted her in the first place:

Original Post (1/12): Charlie Sheen just can't keep Rihanna's name out of his mouth.

During an episode of What What Happens Live on Bravo on Wednesday (January 11), the former Two and a Half Men actor accused the pop star of "abandoning common courtesy and common sense"—all after calling her a "bitch."

When host Andy Cohen asked Sheen if he and Rihanna had ever mended things after the two got into a Twitter spat back in 2014, Sheen blurted out, "Oh, that bitch!"

"I think you just made it worse," Cohen quipped, to which the Anger Management (irony!) actor replied, "No, she abandoned common courtesy and common sense."

Sheen and Rihanna's feud began on the social media platform after the two had an unpleasant run-in (or rather, didn't have a run-in) at a restaurant in 2014.

After the singer declined to meet Sheen and his then-fiancee, Brett Rossi, due to the high level of paparazzi outside, the actor exploded on Rihanna on Twitter, ranting, "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."

In response, Rihanna shared a photo of her signing an autograph for a fan... with Sheen's head Photoshopped in.

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