Nicole Kidman and Keith Urban like to keep things spicy.

On Friday, the couple celebrated their 15th wedding anniversary, and Kidman marked the occasion with a surprisingly racy photo.

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In the pic, posted to Instagram, Kidman’s neck is visible, with Urban licking it.

“Happy Anniversary baby!” she wrote in the caption of the photo, which was taken by famed photography JR.

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Urban also shared a photo to celebrate the anniversary on his Instagram account, though it was decidedly more G-rated, with the two embracing amid balloons and flowers.

In addition, Urban took to Twitter to pay tribute to his wife, writing that “my life started when you said ‘I do’ 5475 days ago today.”

Kidman and Urban have been married since 2006 and share two daughters together. The actress was previously married to Tom Cruise, with whom she also shares two children.