At first, it seems Selena Gomez and David Letterman might not have much in common, but the pair hit it off last night when they bonded over an unlikely cause– making Justin Bieber cry.

Gomez visited the Late Show with David Letterman on Monday (March 18), where she burned her ex with a hilarious diss in front of a roaring studio audience (not to mention the thousands of TV viewers at home.)

When the interview turned to the topic of Gomez’s love life, Letterman brought up the Biebs.

“Now, the last time he was on, uh, he and I got into a conversation,” Letterman said. “He said something and then I said something, and then he said something and I said something, and I made him cry.”

Gomez chuckled and responded: “Well, then that makes two of us.”

To read the entire story, go to Radio.com.