Hikaru Kusakabe is a normal, carefree boy in a rock band who is always focused on the present. During the summer, his entire class is forced to participate in an upcoming chorus festival. By coincidence, he discovers his classmate Rihito Sajou—known for being an honor student with excellent grades—practicing his singing alone. Sajou just cannot seem to get their class' song right, and Kusakabe, delighted at seeing a new side of his straight-laced classmate, offers to help him prepare for the event. Although their lives and personalities are total opposites, they begin to grow closer as time progresses. But with the pressure of an unknown future, what will become of them and their growing relationship? Rihito Sajou is an honor student who got perfect scores in every subject on his high school entrance exam. Hikaru Kusakabe plays guitar in his band that performs at live events and is popular among the girls. These boys would have never crossed paths. But one day Hikaru offers to help Rihito prepare for their upcoming chorus festival and the two begin to talk. As the two meet after school, they feel one another's sound, listen to each other's voice, and begin to harmonize as their hearts beat together.