People magazine said Gaga and Kinney snapped the mirror selfie after having sex on a painting canvas in Chicago. Proceeds from the sale of the issue -- which will be available Thursday and will feature 16 different covers -- will go to raise money for Gaga's Born This Way Foundation.
"I could not complete the covers of this issue without relinquishing one to an important cause," Lady Gaga said.
"Since we first met, Taylor's been painting and drawing all over me. Years ago, when we were secretly living in San Diego and crashing on the floor of a beach shack, we never wore shoes. He told me he wanted to make love to me on a canvas. And though he made many murals on my body in the wee, small hours of our stoked, gypsy mornings with our friends, for whatever reason we never got around to it," she revealed.
Kinney took the photo with a camera to commemorate the day his fantasy became reality. Gaga is seen sitting behind Kinney with her arms around her beau. They are both spattered with paint.