Shuta Aoi, who always dreamed of becoming a hero, was unable to save his childhood friend, Asumi Suido, and gave up on his dream. One year after Asumi's death, Shuta runs into his childhood friends Ran Akagi and Koki Suido at the memorial service. The trio used to be known as "RGB," but they grew apart after the incident. At the memorial, all three of their phones suddenly ring simultaneously. When they look at the screens of their phones, they see that the call is from Asumi, who is supposed to be dead.