Charlie Sheen is absolutely just one of those dudes at the bar who just doesn’t know when to a. shut up and b. go away. Like, dude. COME ON.

It’s pretty clear that Sheen will do basically anything for attention. And the best way to get attention sometimes is to utter the names of celebrities that are way more significant than you. Which is why, I guess, he called Rihanna "a b—h" during a recent appearance on “Watch What Happens Live.”

I’m sorry, what?

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Perez Hilton notes that this beef has been a longstanding one, although it’s mostly been one sided: one time, Rihanna retorted back that Charlie Sheen was an old queen, then went about her business.

But now, Sheen is ready to squash the beef, going as far as to post an apology on his Instagram, offering to buy the multi-platinum Grammy winner a drink sometime.

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Let me tell you something, Charlie. Something it seems like you don’t really know: Rihanna doesn’t have time for you.

Just remember that.