Technically speaking, you cannot steal her bf because he is not her property - he decides for himself what to do, being a citizen of Australia (all citizens of Australia enjoy the ability to exercise their free will).

At the same time, it is a bit socially awkward to stare at someone's pants too much - it is more appropriate to make eye contact and look at the face, from time to time, and at the body as a whole, from time to time, but not focus on the zipper.