Spicing things up!

Lady Gaga and her fiancé Taylor Kinney reportedly had a threesome with his Chicago Fire costar, Monica Raymund.

A source told Radar Online, “I heard the three of them have had a ménage à trois,” adding, “The three of them are definitely up to some sexual hijinks and Taylor is turned on by it all!”

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The American Horror Story actress recently posted a pic with Monica, captioning the photo, “I love her miss Monica Raymund.”

The two women have openly come out as bisexual, so maybe Gaga and her fiancé are not completely monogamous.

Check out our gallery of stars who like to add a little ~extra~ to their relationships.