The story is set in the early 21st century with the population decimated by bio terror. Two kinds of humans now exist. One is the Nokusu who were infected with a virus but survived and consequently they carry an antibody. Most are young, healthy and have high intelligence, but they have a high sensitivity to ultraviolet rays and are active mostly during the night. The other group are the Kyurio. They survived by never having the virus. The Nokusu discriminates against the Kyurio. Tetsuhiko Okudera is a Kyurio. He was born in a poor village. He isn’t happy with being a Kyurio and wishes he could be a Nokusu. Yui Ikuta is Tetsuhiko’s childhood friend. She tries to revive the poor village.
Set within music field, this film depicts a love story between a 25-year-old sound engineer and 16-year-old high school student Riko, who posessess a gifted voice. 25-year-old sound engineer Aki is a member of popular band “Crude Play,” but right after the band decides to make their major record debut Aki quits the band. But, Aki provides his music to Crude Play under the name of producer Soichiro. Aki begins to date Riko, whose father runs a fruit and vegetable shop. Riko doesn’t know about Aki’s background, but she likes to listen to him hum. Riko is in a band herself, with childhood friend Yuichi and Sota. One day she is scouted by producer Soichiro.