After the accidental ingestion of the unusual beverage, its effects start to manifest among Ryuya and his companions, bringing unexpected physical changes and heightened sensitivities to the girls. His sister Miya and the others find themselves in need of relief, prompting Ryuya to offer support through closer interactions. As the urgency grows, the group learns that a lasting solution requires progressing toward a potential vaccine. Ryuya navigates these developments with care, balancing concern for his friends and family amid the escalating situation.