Demon's Among Us Series by Alexander Martin

A partygoer is given the gift of a lifetime at a Halloween party. All of a sudden, his wildest dreams come true, but he never stops asking the right questions about how this lucky streak comes about until it's too late.

Just an average Joe going about his business when he sees a young woman that catches his eye. Of course, she doesn't see him or even glance his way, or so he thinks. When she does start talking to him, he can't believe his luck, but what he doesn't know could hurt him.

A wealthy billionaire picks up a homeless woman off the street and brings her into his house, it is just for one night, or so he tells her. What happens to her after that is her own doing, or is it?