One day after school, the serious Ito and the child-like Nishi meet by chance, as each endeavors to remain walking on the sidewalk's white line. As time goes by, Ito recognizes he is drawn to Nishi in a way that is new to him. Nishi, for his part, is frustrated that they only get to meet on the sidewalk. Ito decides to act upon his feelings and kisses a surprised Nishi, who agrees they need to walk side by side for a change. The sparks between them are undeniable as their relationship blossoms in high school, survives the college years, and matures into adulthood. A deeply moving work that bears witness to loving partners, whose unchanging feelings must co-exist within a world of changing realities.