The pop star fell to the floor when the fan got on one knee.
Katy Perry was feeling the love in Brooklyn.
During her concert at the Barclays Center on Wednesday night, the 32-year-old pop star -- who was dressed in an all-silver costume and Cher-like headdress -- called up to the stage two of her fans for a meet-and-greet that quickly turned romantic.
Perry passed the mic to the fan who was also named Katie and she used the opportunity to propose to her girlfriend, Becky.
In a video taken from a fellow concertgoer, Katie gushes over her girlfriend, telling the crowd, “Well, I don’t know if all of y’all have seen Becky, but she’s pretty even without any makeup on. And she’s perfect every time I look at her."
That's when Katie got on one knee and asked for Becky's hand in marriage. Taken aback by the proposal, Perry's mouth immediately dropped and she fell to the floor.
As the couple started to hug, the "Swish Swish" singer grabbed the mic back and declared, "Say yes, Becky, if you want to get married!"
"My wish came true," Katie said after Becky agreed to marry her.
Thrilled to be part of the engagement, Perry shared a video of the moment on her Instagram Story, writing: "Becky said yes!"
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The heartfelt proposal just so happened to fall on National Coming Out Day which one Perry fan tweeted was so "woke."
It also seemed only appropriate that Perry witnessed the big moment during her Witness tour.
In addition to touring, Perry is also judging on American Idol alongside Lionel Richie and Luke Bryan. In a recent interview with ET, the trio revealed why they'll be better at the job than Simon Cowell.
Check out the video to see their answer: