A Darker Fifty Shades: The Fetish Set (2015) online

Four women gather at a yearly fetish convention in South Texas. Mai, the loving mother who recently began work as a fetish model. Jo, the adrenaline junkie porn star drawn between her new friend Mai and Reyna, an old flame from darker times. Reyna brings along Angel, her new found love and a fresh new face to the industry. As one bad decision leads to another the girls find themselves drawn deeper into a darkness well beyond their rational limits.