Ashton Kutcher Reminisces on His First On-Screen Kiss with Mila Kunis

As we all know, Ashton Kutcher and Mila Kunis's storied romance began when the two played on-screen couple Jackie Burkhart and Michael Kelso on That '70s Show.

Now, almost two decades after the show first aired, and two kids later, Kutcher convinced us that the happily married lovebirds were always destined to be together, as he reflected on his first awkward kiss with the star and how their relationship played out like a rom com IRL during an interview on Howard Stern's radio show.

"It was really weird. I was like, 'Isn't this illegal? Like can I-am I allowed?'" the actor confessed. "It was really awkward because I'm like a 19-year-old kid. I think I was her first kiss, like, on the show. We have our first kiss memorialized on a TV show!"

Though Kutcher didn't have feelings for his co-star at the time, and thought of her "like my little sister," he told the host that he believes the Black Swan star had a crush on him despite her denial.

"She's lying! She has like, a journal or like, a diary from when she was a kid where she wrote, 'Oh, this guy's hot.' She thought I was cute!" he exclaimed.

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When the pair decided to try out their romance off-screen years later, the dad of two hilariously said that their initial relationship mirrored the ones depicted in the duo's very similar romantic comedies: No Strings Attached and Friends with Benefits.

"We legitimately lived out our movies," he admitted. "It was weird and fast. She's like, 'You're not ready to be in a relationship' and I'm like, 'I'm not ready to be a in a relationship.'"

As for the pair's first kiss as a couple, the 39-year-old revealed that the actress used a clever tatic to heat things up.

He recalled: "I think I was smoking cigarettes at the time, and I was still a smoker. She had quit smoking and she was like, she wanted me to like shot gun a cigarette smoke so she could breathe it in and I was like, 'All right.' And I started doing this. And gradually through the night, it got closer and closer and closer."

And the rest, they say, is history.