Sienna Miller was more than surprised by how soon she’d fallen head over heels for her boyfriend, fellow actor Oli Green.

“I didn’t expect to take it seriously and then quite quickly, I fell in love,” the “Burnt” actor said in a Tuesday cover story for Harper’s Bazaar. “I wasn’t like, ‘I’m gonna get a younger boyfriend.’ It was more, ‘F***! Why are you young? That’s so annoying.’”