Marquez is an anthropomorphic skunk, and was a lead biotechnology researcher before becoming a soldier. She was a valued member of the Toxicology Department. Her insight led to major breakthroughs and achievements in the development of toxins and other drugs. However, as her methods moved away from helping people, law enforcement raided the lab. This led to her smuggling the toxin and injecting it into her bloodstream. She now views her body as the ultimate experiment.