Back in February we were a little surprised to hear that Charlize Theron and Sean Penn were a thing. Since then, seeing them together and how happy they look, they’ve actually become our favourite couple. 38 year old Theron has finally opened up about their romance in the June issue of Vogue magazine. The Oscar-winning actress told the fashion bible: “I really didn’t see it coming…It just kind of naturally happened. And before I knew it, I was in something that was making my life better - the people who really love me can see the effect it has had on me.”

Charlize Theron Sean PennCharlize Theron has described her romance with Sean Penn as "effortless"

Theron, who has been on a four year break from dating, explained how a friendship between the two had blossomed into a romance: “Sean and I have known each other for eighteen years…We were just really good friends. And it’s been slow going because you are aware that you could screw that and lose it. We had to think about it. But at the end of the day, it was somewhat effortless.”

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The actress had previously been involved in a long-term relationship with Irish actor, Stuart Townsend. The pair dated between 2002-2010, after meeting on the set of “Trapped” in 2002. While the pair never married, they considered themselves to be. Townsend explained: “We didn’t have a ceremony. I don’t need a certificate or the state or the church to say otherwise. So there’s no big official story on a wedding, but we are married…I consider her my wife and she considers me her husband.”

Penn also split from a long term partner in 2010. He had been with wife Robin Wright, with whom he shares two children, since 1996. In 2012 Theron adopted her son Jackson and is often seen to be a very hands-on mother. Penn has also been spending a lot of time with her son and the trio seem to be forming a happy family together. However, Theron still doesn’t feel the need to walk down the aisle to cement her relationship, “Let’s put it this way: I never had the dream of the white dress…And watching other people getting married? I think it’s beautiful for them, but to be quite honest, usually I’mm sitting there just devastated…It’s supposed to be this night of celebrating love, and all you see is a couple separated all night making sure everybody else is okay.”

Charlize Theron Sean PennCharlize Theron, pictured with her son Jackson, who she adopted in 2012

So, it sounds like she’s not a romantic at heart, although she certainly seems head-over-heels for Penn.  We may have been surprised at first, but after hearing what she has to say, it seems like these two are in it for the long haul.

MORE: Charlize Theron says her son is her number one priority