This drama is a love story between Kataoka Sakuya, a grim reaper who comes to the human world for the first time, and Mochizuki Nayuki, a woman who lost her father at a young age and has devoted her life to raising her only remaining family—her younger brother. As they meet, they gradually come to understand each other, and slowly, they begin to fall in love. However, a fate that will dramatically change their lives awaits them both…
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.