Emergency departments (EDs) are high-pressure care environments in which providing relationship-centered care can be challenging. Patients often wait in pain, fear, and uncertainty, while clinical staff must prioritize urgent cases within time and resource constraints. We propose a patient-facing, ephemeral AI companion designed to support low-acuity ED patients while they wait, without replacing human care. Leveraging the conversational capabilities of artificial intelligence (AI), the companion provides informational and emotional support when staff are unavailable, aiming to reduce feelings of passivity and prepare patients for consultation. We frame this system as a relational mediator that redistributes agency to patients, supports staff through better-prepared encounters, and avoids reinforcing paternalistic models of care. Through this companion concept, we engage with the workshop themes of agents, context and the position of AI, contributing insights into designing AI systems that sustain trust, empathy, and communication in acute care settings.