The 26-year-old actress - who is currently dating Klaxons rocker James Righton - admitted she was "a tomboy" throughout her teenage years, and "hated" girly outfits. She said: "I`ve definitely got a bit of the boyish in me. Growing up I was a tomboy. I didn`t wear skirts until I was 14. I hated them. I love a man`s shirt." Keira - whose new movie `Last Night` tells the tale of a married woman who considers having an affair with a former lover - also explained she had no idea men could be capable of "emotional betrayal" until she started researching the film. She added in an interview with Britain`s Marie Claire magazine: "I really thought women would find emotional betrayal worse and men would consider a physical betrayal worse. "The number of guys I asked said it was the other way round. For them, to love another woman emotionally and not be physical was much worse. "I didn`t think men were capable of emotional betrayal."