Club Luxe Box Set (Books 1-3) (Billionaires Underground) by Olivia Noble

Deep in Chicago's underground, Malcolm Cage runs a sex club for the wealthy elite. The billionaire never participates in the sinful pleasures, and only watches... until he sees her. Intrepid reporter Victoria Chase will do anything for a story. Once she enters the club, she finds herself in over her head, consumed by a dangerous world of passion...