The plot of Hakubo centres around Sachi Koyama, a high school violinist with remarkable talent. Although Sachi is happy with her academic life and has pals in the music club, her favorite hobby is strolling to her bus stop alone in Iwaki, Fukushima. During one of Sachi's after-school walks, however, she has an unexpected encounter with Yuusuke Kijinami, a boy she frequently sees on her bus trip home. After Kijinami offers to assist him in locating a magnificent view of the evening landscape—the subject of his next painting for his art club's exhibition—the two form a friendship through their common admiration for the lovely scenery drenched in sunset. This fortuitous meeting brings together these two souls that hunger for one other.