The two female students from Seohwa School of Arts Piano Department, Choi In-jeong and Seon Kyung-hwa, fiercely compete with each other. Their rivalry, which began in middle school, has persistently continued. Recently, in their senior year, Choi In-jeong, who had always been narrowly behind in piano skill, caught up closely with Kyung-hwa, who began to feel a sense of crisis... In-jeong's obsession with Kyung-hwa, and Kyung-hwa's anxiety towards In-jeong. What could be the reason behind this?