Alberto Ramirez, 37, now faces two counts of rape and other charges.
Both victims say they met Ramirez through social networking websites. The second victim, a 49-year-old woman from Las Vegas, came forward after seeing news reports of his arrest for assaulting a Simi Valley woman.
Prosecutors say he took each of the victims to the same Santa Ana motel, supposedly to perform a body cleansing ritual.
"She began to feel uncomfortable. He put some ammonia on her face. She felt disoriented and dizzy, and then the next thing she knows, he's basically naked and attacking her," said Orange County Deputy District Attorney Whitney Bokosky.
Ramirez faces 75 years to life in prison if he's convicted.
If you have information about Ramirez, contact Orange County Crime Stoppers at (855) TIP-OCCS.