Rihanna unknowingly took part in a romantic proposal when a fan of the R&B singer got down on one knee before his girlfriend during a backstage meet-and-greet on her 2011 Loud tour.

According to Idolator, the red-haired pop star was graciously posing for photos with members of her Navy when a couple sauntered up for their pics. Before Rihanna knew it, the man had taken out a small blue Tiffany's box and asked his girlfriend for her hand in marriage in front of the unsuspecting star.

Judging by the photos, Rihanna was the most shocked out of the three, looking wide-eyed and bringing her hands to her face during the proposal. The woman said yes (how could she say no in front of RiRi?), and showed off her stunning solitaire for the camera.

The R&B songbird then posed for a memorable photo with the just-engaged couple, looking jealously at the woman's freshly iced ring finger. Talk about one for the scrapbook! Will Rihanna make it to the wedding? Anything's possible, but one thing's for sure -- she's definitely on the guest list.

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