Cature Inoshee is the illegitimate child of the Issue family head and a servant, whose pregnancy led to her expulsion. This hidden lineage emerged only after the death of the legitimate heir, Carta Issue. When the family's chief retainer, Okina Uroka, tried to install Cature as the new heir, she refused and fled to escape both the Issue family and Gjallarhorn.

She harbors intense animosity toward Gjallarhorn, speaking bluntly unless the organization is involved. Questioning her dislike prompts various excuses, though frequent blunders when discussing Gjallarhorn betray a deeper, unresolved connection linked to her origins and her mother's treatment. With no destination after fleeing, she stowed away on Wistario Afam's ship during his Urdr-Hunt journey. Having nowhere else to go, she joined Wistario as a companion for his quest while on a break from her studies. She intends to return to her education and later reunite with Wistario at Radonitsa Colony on Venus.

Cature is part of Wistario Afam's "Afam Equipment" group, participating in the Urdr-Hunt—a high-stakes competition offering a colony-scale reward. Her involvement places her alongside factions like the Omden Colony Company, Foundling, Rakow Pirates, and Zahn Clan within the narrative.