When Mila Kunis starts a conversation with, "I don't even know if I'm supposed to tell this story; I might get in trouble for this," you know it's gonna be juicy.

On Tuesday's Howard Stern Show, Kunis opened up about her marriage to Ashton Kutcher — her first on-screen boyfriend in That '70s Show. The happy couple is now expecting their second child, but their relationship wasn't always super romantic. In fact, they were once Friends With Benefits who hooked up with No Strings Attached. Yep, just like in their movies.

"If we just paid attention to these movies, we should know that shit like this does not work out in real life," Kunis said about their first night together. "Well, we clearly didn't pay attention and we shook hands, we're like, let's just have fun. I mean, literally, we lived out our movies."

So how did this all go down, exactly? Rewind to 2012, when Kutcher was newly divorced from Demi Moore, and Kunis was also fresh out of a long-term relationship. Neither were interested in something serious. The two friends kept in touch over the years via AIM — remember that? — before running into each other at an awards show. Kutcher invited her to his housewarming party, where she eventually had this brilliant realization: "Fuck, he's good looking."

"For the first time ever, [he] took my breath away. Like that's the best way I could describe it," she revealed. "Long story short, I didn't leave 'til the next morning."

"We both were in agreement like yeah, this is just fun. Three months later, I was like, this isn't fun anymore," she continued. "We found out we would literally go out and attempt to go see other people, and then literally that night we'd just be like, hey what are you up to? Want to come over?"

But things don't always go so swimmingly in friends-with-benefits situations. So what's the secret to making it work? According to Kunis, it's all about being honest about your feelings. They had a lot of "open conversations" with each other, and she said their relationship "could not be anymore transparent."

"We ended up having a lot of talks about how this is a huge mistake and how he needs to go and be single, and I need to go and be single," she said. Three years later, they tied the knot. Funny how life works out, isn't it?

Listen to Mila's full interview with Howard Stern below.