Eric Charbonneau / WireImage 1 / 15
Eric Charbonneau / WireImage 1 / 15

It's been nearly a year since Jennifer Aniston and Justin Theroux went public with their romance.

And now that the "Wanderlust" co-stars are living together in a Hollywood Hills, Calif., rental -- and prepping to move into a massive, $21 million home in the Bel Air section of Los Angeles -- Aniston, 43, continues to open up about why Theroux, 40, is a keeper.

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"He's a protector, for sure," Aniston tells the May issue of Marie Claire Australia (excerpted in Just Jared) of actor and screenwriter Theroux. "He's just a good human being, and so funny."

As reported by Us Weekly last year, Aniston and Theroux first fell in love while making "Wanderlust" in rural Georgia in fall 2010; at the time, Theroux still had a long-time live-in girlfriend, Heidi Bivens.

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Aniston told Marie Claire Australia said she "began decompressing" during the secluded shoot. "It's weird, but it felt like living a normal life; almost like having your anonymity back. Nobody bothered us and we were protected as a group."

The stunning star famously shot a topless scene for the raunchy comedy, which was a box office and critical bomb in the U.S. earlier this year.

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"There are always nerves when you shoot a scene like that," she admitted. "But the adrenaline takes you through it and then you have the girls come in and cover you up immediately."