True agency for the isekai companion manifests either as a violent rejection of dependency or a calculated mastery of it. While both characters operate in the shadow of dominant protagonists, they represent opposite philosophies of survival. Eris views her initial inadequacy as an intolerable failure, leading her to abandon her domestic security for a brutal, multi-year training regime. This trajectory transforms her from a volatile noble into a YPS-3 asset capable of threatening entire cities, proving that her high Growth score is a direct result of her refusal to remain a narrative accessory. Conversely, Visha treats her position as an indispensable cog in Tanya's machine not as a lack of ambition, but as a professional survival strategy. Her YPS-2 status is sufficient for her goals because her value lies in logistical stability and emotional labor rather than destructive output. The comparison breaks down when analyzing Ego; Eris fights to define herself against her environment, whereas Visha finds peace by integrating into it. Eris's path is one of escalation, while Visha's is one of endurance. One seeks to stand beside the lead through parity of force, the other through parity of necessity.