Chester, Emilia’s father, single-handedly raised her after unmentioned family upheavals. As Emilia matured, their bond frayed, her growing independence driving a wedge between them. A scientist linked to a Magmell research facility in the seventh ward, he vanished after becoming trapped there, compelling Emilia to seek outside aid. Before his disappearance, he advised her to reach out to Inyo for help—a directive she mistakenly attributed to Shuin initially.

Freed from captivity, Chester’s research aligned with corporate ventures encroaching on Magmell’s resources, clashing with the Erin, Magmell’s indigenous guardians, who viewed his work as a threat to their land. Emilia later enlisted Inyo to negotiate between her father’s employer and the Erin, though the resolution of this mediation remains undefined.

Chester’s appearance—marked by a beard, dark blonde hair, and olive eyes—reflects his pragmatic demeanor, fitting his scientific vocation. Beyond his strained ties with Emilia and career-driven conflicts, earlier life details and post-rescue personal developments remain unelaborated.