Combs kicked off in a Manhattan courtroom on Monday, with federal prosecutors trying to prove he turned his hip-hop conglomerate into a racketeering enterprise that forced women to satisfy his sexual desires for two decades.

Sean “Diddy” Combs’ ex-girlfriend, Cassie Ventura, began what could be a days-long testimony in Combs’ sex trafficking trial Tuesday, alleging on the witness stand Combs had subjected her ...