Former clean-cut Disney star Cyrus, 19, filmed the bedroom scene with British actor Booth, admitting kissing him "could be worse."
On her co-star's looks, Cyrus tells Britain's The Sun, "He's gorgeous. He's like one of the coolest dudes ever. He's really funny. We called him 'Princess' because he has a very posh English accent. It seems like old Shakespeare or something."
However, the star struggled to prepare herself ahead of filming, admitting it was a unique experience.
She says: "It was the first scene we shot together. First day, and it was the sex scene. I forgot to shave my legs. I was in the trailer and I was like, 'Give me a razor, quick'. It was really funny having someone lie with the camera and saying, 'OK, put your leg in your hand. Can we see movement?'."