Their American horror story may have just turned into an American love story. “American Horror Story” stars Emma Roberts and Evan Peters are reportedly engaged, the Extra wrote on Monday.

Peters got down on one knee while the couple celebrated Christmas in New York, the site reports. They then flew across the pond to celebrate New Year’s in London. The Extra said Peters, 26, traded in Roberts’ promise ring for a pink and gold diamond sparkler. The two FX co-stars have been dating since 2012.

There is no word when the pair will wed, but they haven't always had the smoothest relationship. As the Daily Mail reported, they made headlines last year when Roberts, now 22, was arrested on a domestic violence charge after she got into a fight with her beau. She was taken into custody in July in Montreal after she supposedly left Peters with a bite mark and a bloody nose. Peters didn’t press charges and has since referred to Roberts as the “love of my life.”

At the time, a rep for the couple told Us Weekly that it was a “misunderstanding.” The statement rep’s read: "It was an unfortunate incident and misunderstanding. Ms. Roberts was released after questioning and the couple are working together to move past it.”

A source told Us Weekly Roberts can be “very dramatic” and that she can get “wound up” during arguments. In reference to the fight in Montreal, the insider said things got “way out of control.”

“They're a couple young kids," a different source said, adding they were “inseparable.” "Their romance is pretty extreme. They just behave in a way that's very passionate."

“American Horror Story” shows on FX every Wednesday at 10/9c.

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