A demonic conversion is a ritual where mortals, half-demons and other beings can become pure demons. A complete conversion would presumably destroy the soul, causing them to lose the ability to feel emotions like love. A conversion may cause physical changes, as seen with Sirk. When he gained a more reptile-like appearance as his conversion advanced. Once completed, a demonic conversion cannot be undone.
Types of Conversion
Demonic Training Program
Mortals are recruited into a Demonic Academy and have to follow a brutal training program. They earn chevrons which represents the status of their conversion. In order to complete this conversion, the mortal has to kill another mortal.
Killing Mortal Relatives
The half-demon Sirk, had to kill each mortal relative in order to become fully demonic. With each kill he would get another power until he killed the last relative. During the conversion, he would turn into his demonic self and lose his mortal appearance.
In one instance, a woman had an affair with a married man, but when they were caught the man was held blameless while the woman burned at the stake. The townswomen cheered as they burned her, and her rage turned her into a demon known as the Siren, who killed couples by seducing the men with her enchanted song, incinerate their lungs with her Kiss of Death, and then destroy the couples with Pyrokinesis.