Megan Fox Made a Surprise Appearance at Machine Gun Kelly's Concert in a Bra Top

Another day, another outing for Megan Fox and Machine Gun Kelly. After walking the red carpet together at not only the Billboard Music Awards, but also the iHeart Music Awards, the couple capped off their whirlwind week with a PDA-filled appearance at the Indianapolis 500.

On Saturday, MGK (whose real name is Colson Baker) performed at a concert ahead of the race, and Megan surprised fans by joining her boyfriend onstage. During his performance of the song "I Think I'm OKAY," Kelly introduced Fox — dressed in a black bra top with long sleeves, high-waisted jeans, and platform heels — to the audience as his "girlfriend."

She wore her long hair down in loose waves and parted down the middle.

In a video shared to Twitter, Megan held MGK's hand and kissed his shoulder, before running off when he turned the microphone towards her to sing.

Earlier this week, Kelly revealed the exact date Fox told him "I love you." On Tuesday, he tweeted: "She said 'I love you' one year ago today." Fox also hasn't been shy about her and Kelly's connection. Back in November, she told Nylon that "loving him is like being in love with a tsunami or a forest fire."

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She elaborated, "The intensity of merging with him is just overwhelming, and the threat it poses is so powerful but so beautiful that you have no choice to surrender with reverence and with gratitude."

Meanwhile, Kelly said he fell in love "for the first time" when he met Megan. "That was my first experience with being open to love and stuff like that," he previously revealed while appearing on The Howard Stern Show. "I definitely wasn't set up to believe that that's something that could ever exist."