After they, too, tried to dissuade him, he became furious and put their three names on a proscribed list of people to be executed the next morning, along with prominent senators. Commodus, upset by Marcia's reaction, then told his plan to Aemilius Laetus, the Praetorian prefect, and Eclectus, his servant. After telling his plan to Marcia the night before, she begged him not to behave so carelessly and bring disgrace to the Roman Empire.

To celebrate the Roman New Year in AD 192, Commodus decided he wanted to make an appearance before the Roman people not from the palace in traditional purple robes, but from the gladiator's barracks, escorted by the rest of the gladiators. The inscription found in Anagnia testifies that the local city council decided to build a monument, commemorating particularly the restoration of baths on her account. Despite the fact that Marcia was not Commodus' legal wife, he treated her like one and was thus greatly influenced by her. After Victor gave her a list she had asked for including all of the Christians sentenced to mine works in Sardinia, she convinced Commodus to allow them to return to Rome. Marcia had Christian sympathies and persuaded Commodus to adopt a policy in favor of Christians, and kept close relations with Pope Victor I. Marcia managed to escape charges, and after Commodus' wife Bruttia Crispina was exiled and murdered due to adultery, Commodus chose not to marry again and took Marcia as his concubine.

The plot was discovered and both Lucilla and Quadratus were executed. In AD 182, Lucilla, the sister of Commodus, convinced Marcia to join in a plot with Quadratus to kill Commodus. Commodus' favourite mistress īefore Marcia was Commodus' mistress, she was the lover and mistress of one of his cousins, Senator Marcus Ummidius Quadratus Annianus, and subsequently a wife of his servant Eclectus. Marcia was likely to have been the daughter of Marcus Aurelius Sabinianus Euhodius, a freedman of the co-emperor Lucius Verus. Marcia Aurelia Ceionia Demetrias (died 193) was the mistress (182–193) and one of the assassins of Roman Emperor Commodus. Mistress of Roman emperor Commodus (died 193)

Mistress of rome