Lilium is a blonde-haired elf girl inhabiting the fantasy world of the story. Her first encounter with the protagonists occurs at the "Onsen of Death," a location feared by her people; mistaking them for demonic entities while they bathe, she launches an attack. This initial conflict finds resolution through their later interactions. Her sister, Ōhendeku, leads their elf tribe as chief. Facing dire financial hardship in their village, Ōhendeku pursues economic aid by developing the hot springs. Lilium actively contributes to these crucial discussions, specifically collaborating on conceptual blueprints to transform the Elf Village into a thriving hot spring town, envisioning layouts and atmospherics. Details about her life before meeting the protagonists, her role in events outside the main series, or her development in other media remain undefined within documented events.