Satoshi Kubo has been dubbed the "God of Death" since he was a child. Whether relatives or friends, as long as they get close to him, they are bound to suffer a catastrophe that is enough to lose their lives. Over time, in order to protect friends and relatives, Satoshi gradually got used to the life of being alone. By chance, Satoshi rescued a girl named Mizuki Sawai. Satoshi's silence and mystery gradually attracted the strange personality Mizuki, who launched a fierce attack on her. In order to protect Mizuki, Satoshi decided to hide his throbbing feelings. However, Mizuki's bravery and perseverance allowed Satoshi to finally accept this dangerous feeling. He hoped that true love could break the curse on him. The good times didn't last long, Mizuki contracted cancer and eventually died in pain. Satoshi could no longer find a reason to continue living, he decided to end his life.
Sakuragi Rino is a high school student. She is good friends with Kiritani Ren, who attends the same high school. Close since their middle school days, Rino has special feelings for Ren; however, she is unable to tell him how she feels. One day, Ren confesses to Rino that he likes her. They begin to date and enjoy their time together. One day, Rino is diagnosed with ALS (amyotrophic lateral sclerosis)
Rainbow Song is a beautiful, yet tragic love story about a romance that never happened. Two young film students, Tomoya and Aoi, become fast friends after being put on a project together. Quickly, Tomoya becomes enamoured with the young girl but is too afraid to tell her his true feelings. After graduation, Tomoya continues living in Japan working on a film set and Aoi leaves to work in America. The movie takes a turn as Tomoya finds out that Aoi never made it to her destination because of a plane crash. He then starts to become consumed with his thoughts, day-dreaming about the love affair that never was nor can be
