Valyn originated as a prototype Lævateinn series unit engineered for combat, yet possessed an inherently gentle and kind personality. She formed a profound bond with Tyrfing, another Lævateinn unit she regarded as a younger sister.

A defining mission shattered Valyn's early existence: witnessing Tyrfing's brutal death. This trauma scarred her deeply. Valyn subsequently vanished and was presumed dead.

Years later, she reemerged under the name Durin, serving as a commander within the "Garden" organization. As Durin, she exhibited a cold, ruthless demeanor and strategic brilliance, a stark reversal of her former gentle nature. Memories of her past life as Valyn, including her connection to Tyrfing, appeared suppressed or lost.

Durin commanded Garden's Killer Phantoms with ruthless efficiency, pursuing the organization's goals with unwavering determination and emerging as a primary antagonist.

Interactions with Tyrfing, who survived their shared tragedy, gradually triggered the resurgence of Valyn's past identity. Fragments of memory and emotional responses pierced Durin's controlled facade.

A pivotal confrontation ensued where Tyrfing directly challenged Durin, forcing a reckoning with the suppressed memories of their shared past and the witnessed death. This clash triggered the collapse of the Durin persona.

Valyn regained her true memories and identity. Overwhelmed by the resurgent trauma and the actions committed as Durin, Valyn chose to end her own life, expressing a desire for peace and reunion with her fallen sister.