The boys were performing on The Late Late Show, when Ari came out from backstage to sing along to their rendition of “And I Am Telling You I’m Not Going.”
“Oh my God!” Francis exclaimed, dropping to his knees before getting back up to hug her.
They then continued to sing together.
“You’re like, ‘Please stop talking, we wanna take a selfie,’” Ariana joked in a video.
“It was so nice to meet and sing with you guys!” she told them.
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