Being the sister of Florretta Dela Rosa Mors, Sissilya shares her sisters pale skin and purple hair, though Sissilya's is a little darker and of a different hairstyle. She is just as interested in science as her sister and will often run experiments with the strangest things imaginable.

She has no respect for anything and everyone but her sister is just a means to an end, or to satisfy her own curiosity, meaning if you are caught, you are her experiment.