The "Gravity" hitmaker admitted she was "flattered" to be asked to front the fragrance but did not feel nervous about taking over from the superstar, reported Contactmusic.
"It wasn't a case of filling her shoes. I'm honoured to be in the same line-up as her and didn't feel threatened or scared," she said.
However, the 21-year-old raven-haired beauty confessed she found filming the sultry ad for the scent, which features her kissing a male model, quite challenging.
"He made me feel very comfortable but kissing a stranger with 20 people in the room was new experience to me," she said.