A former member of an alleged New York sex cult testified on Wednesday that the secretive group's leader forced her into an unwanted sexual encounter and took nude photos of her after he announced that he was her "grand master."

The leader of the Nxivm group, Keith Raniere, 58, is charged with ordering numerous women to have sex with him, branding them with his initials and forcing them to adhere to a near-starvation diet.

Sylvie, a 32-year-old British woman who testified under her given name only, is the first alleged victim to appear as a witness at Raniere's trial in U.S. District Court in Brooklyn.