Britney Spears and boyfriend Sam Asghari made their red carpet debut as a couple.

The "Oops I Did It Again" singer and fitness model, who have been dating for almost three years now, attended their first movie premiere together on Monday (July). The pair made a surprise appearance at the Hollywood premiere of Once Up a Time in Hollywood, where they looked more in love than ever as they posed for photos together.

They even shared a sweet kiss:

Matt Winkelmeyer, Getty Images

To celebrate the big night and red carpet debut, Spears rocked a red, one-strap mini dress, paired with black heels and a silver choker, while Asghari sported a cream-colored suit and black tie.

Spears commemorated the moment by sharing a few photos on Instagram, writing, "Our first premiere."

Fans also noticed the pop star was wearing a diamond ring on that finger, leading many to believe the two might have secretly got engaged. Of course, it's all just speculation for now, but we wouldn't be surprised if Asghari popped the question. In the last year, he's been one of Spears' biggest supporters after she checked herself into rehab, as well stood by her side during all the drama with her father's ongoing conservatorship.

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