Nightstar by Fern Michaels

Caren Ainsley was plucked from obscurity to be the face of Nightstar, the hot new perfume from Rayven Cosmetics.  More than that shes fallen for Marc Rayven.

This book was published in 1984, so it was one of Fern's earlier works, but still great reading.  This was a re-release HQN series this month.  Its a two-in-one deal.  (But I have not read the next book!)