It all started when Rihanna apparently declined to meet Charlie Sheen's fiancé Brett Rossi -- the "Diamonds" singer now reacts to the "Anger Management" actor's Twitter rant.

Sheen revealed that he was taking porn star Rossi out to dinner for her birthday at Giorgio Baldi restaurant in Santa Monica on Wednesday evening, May 21. He found out that the Barbadian singer was eating nearby, and then put a request to meet her. However, he became furious when Rihanna allegedly declined.

Consequently, the 43-year-old actor took to his Twitter account the next day to post a long, detailed rant, aiming at the 26-year-old pop star. His tweet is as follows:

Rihanna was not going to just sit around and do nothing about Sheen's Twitter attack, as she posted a series of tweets seemingly referring to him. "Goooorrrrrrlllllll...... If that old queen don't get his diapers out of a bunch," she wrote.

The "Pour It Up" hitmaker also posted two combined photoshopped snaps of herself with one version putting an arm out to stop another version. "When I'm about to go off and my subconscious be like: nah, Chill B," she wrote the following caption.