Sakutarou "Saku" Matsumoto is just an average guy traveling to Australia to spread the ashes of his deceased girlfriend, Aki Hirose, over Ayers Rock—a place she wished to see before she passed. On his journey, Saku reminisces about the first day he met the popular Aki in middle school, their budding relationship, and the leukemia diagnosis that cut her life short. Sekai no Chuushin de, Ai wo Sakebu depicts a melodramatic romance between two young individuals as they grow up and learn what love truly means to them.