Faith

Faith is a lifelike robot who took part in the murdering of Nicholas Monrova and his family.

History
Faith was one of the Lifelikes that lived together with the Monrova family. She was extremely close to Ana after whom she had been modeled. After her "brother" Gabriel was infected with a nanovirus and sent to kill everyone who stood in the way of Nicholas, Gabriel infected his fellow Lifelikes as well and together they seized Babel's upper levels and captured - and ultimately killed - the Monrova family. Faith herself was responsible for killing Olivia. Still, Ana survived with life-threatening injuries and was rescued by Ezekiel and Silas.

Two years later, Faith was sent to capture Silas, but found out that Ana - now under the name of Eve - was still alive. She wanted to take the girl back, but only managed to seize hold of Silas and thus kidnapped him instead.

Trivia

 * According to Ezekiel Faith is a terrible liar.
 * Faith is modeled after Ana Monrova.