Mala was a Vidiian female, and former childhood friend of Danara Pel.
When Danara was nine years old, two years after contracting the phage, she learned that Mala no longer wanted her to come to her house anymore because Mala was afraid of Danara.
This memory haunted Danara for the rest of her life, and would be recalled when she discussed committing suicide with The Doctor. (VOY: "Lifesigns")
This character was only mentioned in dialogue.