Helga Piraroza is a mage serving under Villar Constance. She is visibly distressed upon learning of the overwhelming Nordic and Marrine Kreische forces besieging Castle Unicorn, yet retains her composure when Villar issues commands. Her loyalty to him is clear when she obeys his order to heal injured enemy soldiers despite the siege's dire straits.

During the castle's fall, Helga provides Laura Hardley with a vial of presumed lethal poison, enabling Laura to avoid capture by Milza Kuces's forces. This act implies Helga's own death or capture. However, the poison is later revealed to be non-lethal, allowing Laura to survive and enter Eudokia Colorha's service. Laura's reappearance confirms Helga's survival, though Helga's specific role in this outcome remains unrecorded.

Helga possesses violet hair and olive eyes. Her origins, activities after the siege, and involvement in other official media beyond these events are unknown.