AceShowbiz -

Taylor Kinney recalled the first time he kissed his now-fiancee, Lady GaGa. Sitting down with Andy Cohen on Bravo's "Watch What Happens Live!", the actor said he was slapped by the singer when he first smooched her.

Their first kiss happened on the set of the Mother Monster's "You and I" music video back in 2011. "I showed up and [producers] said, 'Oh, this is the idea.' And I said, 'Okay, just let me do my thing,' " said the "Chicago Fire" star.

"I remember I went up, and we're rolling, and I kissed her and she didn't expect it," he said. "They cut, and she slapped me. And it was just awkward. And the next take, I just did it again and then she didn't slap me. She didn't slap me then."

He continued, "We had a good time. I think there was chemistry. It was a late shoot. We were shooting until 4 or 5 in the morning. We exchanged information. A few weeks went by and we kept in touch and then that's that."

The couple became engaged on Valentine's Day this year. Of their wedding, he said, "We're so busy. We've been engaged for less than a year. So, we've been talking about whether it's New York, Los Angeles, destination place so we don't have an exact date yet."