Sean "Diddy" Combs used fame and violence to sexually abuse women, prosecutors have said in opening statements at the hip-hop mogul's trial, while the rapper's attorneys defended his "swinger" lifestyle. The 55-year-old has pleaded not guilty to charges including racketeering, sex trafficking and transportation to engage in prostitution.

Who is Cassie? Casandra Ventura is the R&B singer and actor who started testifying Tuesday in Sean “Diddy” Combs sex trafficking trial. She is known simply as Cassie.

The long-awaited proceeding in federal court in Manhattan kicked off Monday with opening statements. Prosecutors painted a picture of Combs as a violent individual running a criminal enterprise, based on coercing people — using drugs, threats and physical force — to participate in orchestrated sex acts called "freak offs."