Yes - it is your g/f who is applying for the visa - the employer is just her sponsor. She needs to sign the application form ID990A and her employer the sponsor's form ID990B. See The Government of the Hong Kong Special Administrative Region - Immigration Department
EDIT _ Actually, the forms have changed recently, and, strangely, I now see that they really are two separate forms, and the Applicant DOESN'T actually need to make any reference at all to the sponsoring company on the form that they fill in. Which is really very strange. And, to me, wrong.