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.

Sean "Diddy" Combs' ex-girlfriend Casandra Ventura, a rhythm and blues singer known as "Cassie," is expected to testify on Tuesday as the prosecution's star witness in the hip-hop mogul's sex trafficking case,