The Guide: Rosita Farisi

 Name: Rosita Farisi

Home Planet: Earth

Home Era:19th century

Appearances: DW: The Next Doctor

Actor:Velile Tshabalala

Information:

Rosita was a young woman who lived in the 19th century and was saved by someone who belived he was a man called The Doctor. In reality he had been living a lie and was in fact just a human called Jackson Lake who had used an infostamp to defend himself against The Cybermen, but the device backfired, filling his mind with information the Cybermen had gathered on the Doctor. The two of them noticed that peole were going missing and decided to team up and investigate. She met the real Doctor when her and the other Doctor Jackson Lake tracked down a Cybershade. The real doctor explained the truth to them and that he was in fact The Doctor. After that the Cybermen and their human accomplice Miss Hartigan put their plan into action using orphaned children to bring around the rise of the cybeking. Rosita helped The Doctor and Jackson by freeing the children and even punching Miss Hartigan in the face!The Cyberking was destroyed and Rosita went away she went to live with Jackson Lake and his son who he found in the Cyber workhouse.

Also:

1.According to a interview with Velile Tshabala who plays Rosita said she was a prostitute before meeting Jackson Lake. This is hinted at in the episode when Rosita and the Doctor confront Miss Hartigan and she replies to her by saying, 'You can be quiet; I doubt he paid you to talk'. 

2.Rosita's name was decided on because it contains elements of the names Rose and Martha. It is also Spanish for "little rose". 

3.Her second name is never revealed in the episode but is given as Farisi in the reference book Doctor Who: Companions and Allies