During day 12 of the Jody Arias death penalty retrial, the jury heard more testimony about explicit email and text message exchanges between Arias and her former boyfriend, Travis Alexander, before he was murdered.

Earlier this week, defense witness Dr. Miccio Fonseca, a clinical psychologist who specializes in twisted sexual behavior, testified about Alexander's inner conflict between his religious conviction and sexual desires. While on the stand, Fonseca stated that Alexander had a mastery of deception and a "Dr. Jekyll and Mr. Hyde" personality. She also alluded that he communicated having sexual desires about minors, reports ABC 15 Arizona. As a result, her testimony served to build the defense's argument that Alexander was a sexual deviant who emotionally abused Arias.

On Thursday, Fonseca returned to the stand, testifying that Alexander degraded the convicted killer and made her feel like a prostitute. She also spent time reading parts of a long instant-message exchange between Alexander and Arias where he called her a "whore" and a "solid form of evil," reports AZ Central.

However, sparks flew in the courtroom when state prosecutor Juan Martinez stepped up to cross-examine the psychologist. Martinez used two documents to point out similarities and differences in her testimony. He also handed her a document of an interview with Arias' brother, Carl, whom Fonseca confused with her father, Bill.

"You seem to be having problems with your memory," Martinez said during his cross-questioning.

According to court watcher Jen Wood, the cross-examination "was really intense and really heated."

"Dr. Fonseca really challenged Martinez, saying, 'You're mischaracterizing everything I say, for every question he asked her,'" she said according to KPHO.

Debate over deleted pornography from Alexander's computer also continued on Thursday as Arias' lawyers filed a response motion to the prosecutor's counter claims made earlier this week, reports USA Today.

In May 2013, Arias, 34, was convicted of brutally murdering Alexander, 30, inside of his Phoenix, Arizona, home in June 2008. According to medical examiners, Arias stabbed him 27 times, primarily in the back, torso and heart. She also slit his throat from ear to ear, nearly decapitating him and shot him in the face.

Although Arias was found guilty of first-degree murder charges, the jury failed to reach a unanimous decision on her sentencing. As a result, the jury in her retrial will determine whether she should be sentenced to death, life in prison or life with a chance of release after serving 25 years.