Donna, originally named Angelica Klein, was a researcher experimenting with autonomous DZ machines. During a seventeen-day lab trial, a DZ replicated her personality, triggering a severe psychotic break that shattered her psyche. This trauma led her to adopt a new identity as the mercenary "The White Death."

Hired by Hans Andrei, her mission was to locate and eliminate Derrida Yvain, the central figure in conflicts arising from flawed DZ programming. She pursued this objective using knives and firearms in close combat, though her tactical choices during engagements could seem erratic. Her allegiance ultimately shifted; she betrayed her employers by aiding Derrida at a crucial moment, enabling his escape and survival. This betrayal marked a significant turning point. Her transformation from researcher to mercenary, driven by the psychological trauma of the DZ integration incident, underpins her motivations and actions.