L. Marie Adeline 
The Secret Trilogy: Secret / Secret Shared / Secret Revealed 

Cassie’s life rarely takes her by surprise. She waits tables at the rundown Café Rose in New Orleans, heading home alone each night, yearning for more from her life and wishing she could make it happen.
But when Cassie discovers a notebook left behind by a mysterious woman at the café, her world is changed forever. The notebook’s stunningly explicit confessions shock and fascinate her, and eventually lead her to S·E·C·R·E·T, an underground society dedicated to helping women realize their wildest, most intimate sexual fantasies. At the heart of the society is three rules:
NO JUDGEMENTS. NO LIMITS. NO SHAME.
As Cassie is set free from her inhibitions, she is transformed by the confidence she didn”t know she had. And so begins the most surprising experience of Cassie”s life as she finds her place in an enticing world of passion and danger, with the power to have any secret wish become a reality…
If you can”t wait to see the Fifty Shades film and have devoured all of Sylvia Day”s Crossfire series, the SECRET trilogy will become your new addiction.