When Tsumugu was young, he shared his adventurous tales with his bedridden friend Saguri, who yearned to explore the world. Promising to embark on a grand journey together, fate separates them before they can fulfill their pact. Years later, Tsumugu unexpectedly reunites with Saguri at their new school. Encountering her after a collision, Saguri rekindles their old promise, leading them to an abandoned quarry where unpredictable revelations await the once-dreaming duo.