They meet when a mutual friend points Serena in Damon's direction to have a fantasy of her own fulfilled. After meeting with Damon, Serena emails him information on her sexual fantasies, which involve her being a sex slave. Damon, who wants a slave of his own, is interested in her and decides to take on her fantasies himself whether than providing a list of members from his club who will be willing to be her Master.
I think the book is well written, however it is a little heavier in sexual slavery than I care for. While he vows to protect her and that she should only see him, there are other men involved and he engages in activities which result in her crying. While most of the scenes in the book apparently came from fantasies she emailed him, I would have preferred things be a little less hardcore than I think they were.